One of the big issues in epistemology is the problem of infinite regress. "I believe the sun will rise." "How do you know that?" "Because it always has." "How do you know that?" "Because my memory and human records confirm it has." "How do you know that?" "Because I've examined those memories and records." "How do you know that?" And so on. It looks like this could go on forever. It seems like any answer you give can be doubted. We can always keep asking "How do you know that?" And this isn't the only line of regress. "I believe the sun will rise." "How do you know that?" "Because it always has." "How do you know something that's always happened will continue to happen?" And so on.
The difference between these two lines of questioning is that the first is about the facts, while the second is about which rules are valid when interpreting those facts. Every rule is doubtable, because exceptions are always possible, and every fact is doubtable, because we could always be mistaken, someone could always have made an error, or lied, or our memories could be inaccurate or false, and so on. Thus, the problem of regress is just this: Where is it reasonable to stop doubting, to stop asking questions? When should we just shut up and believe?
Chris says "I do not think that Carrier has escaped the problem of regress" because "no line of reasoning can ever get us out of skepticism regarding memory, because in order to reason we must be able to remember the previous steps of the line of reasoning" and therefore, Chris concludes, "I think [Christian apologist Alvin] Plantinga has hit upon the only real solution to the problem of regress." Chris acknowledges but doesn't say enough about my refutation of Plantinga's proposed solution in Sense and Goodness without God (especially on pages 43-47 and 184-85).
What is Plantinga's "solution"? Simply to assume Christian Theism is true, and that we are fully justified in assuming this without needing any evidence Christian Theism is true. "I don't need a reason to believe it." Silly, you might say, but a number of Christians agree with him and are marching along to the same tune. In his own attempt at a solution (on a subsequent blog entry), Chris says "though one belief may be occasionally traced to another, there must always be givens, or else we fall back into the problem of regress," which I likewise argue. Yet I could not find any actual solution to this problem on his blog.
Chris seems to say that all we need do is just arbitrarily assume some things, but he never explains what things we are allowed to assume, or why it is okay to assume those things, and not others, or a smaller set of things to begin with. He recognizes this as a problem for Plantinga--as Chris says, if we get to assume Christian Theism is true, then we could just as easily assume Great Pumpkinism is true, so where does that get us? But if we can't just start with assumptions like those, because they are dangerously and irresponsibly arbitrary (and they are), then what assumptions can we start with? Chris doesn't say. That's not a solution.
In contrast, I did offer a solution. And it works. Chris thinks it doesn't, but he seems to have missed several elements of my epistemology, although not everything he missed is adequately explicit in my book. So here's a clearer exposition on the subject.
First, I discuss radical skepticism a bit more in Sense and Goodness than Chris seems aware, and in ways directly pertinent to this discussion. Just look up "Cartesian Demon" in the index and read every passage listed there. It's important to understand what a Cartesian Demon is, and why we are justified in rejecting the existence of such a thing. Basically, a Cartesian Demon (or CD) is anything (intelligent or otherwise) that meddles with our perception and memory in exactly such a way as to consistently mislead us into false conclusions. It's the big "Well, what if someone planted all the evidence!?" objection to every conceivable claim. It needn't be a "someone," either. We could just as easily say something like, "Well, what if an undiscoverable conjunction of physical laws and processes is misleadingly creating all the evidence?" Either way, we're talking about an appeal to a Cartesian Demon.
Experiences are Not Limited to Sensory Perceptions
Second, in Sense and Goodness I specifically include emotions and thoughts among basic experiences (e.g. page 30). So despite what Chris implies, I did not ignore "interpretations" in my category of "perceptions," since "interpretations" are experiences of thoughts, and those thoughts are properly basic. What do I mean by that? To say something is "properly basic" is to declare that it's something we get to assume without needing a reason to believe it. In my epistemology, however, in direct contrast to Plantinga's, only what is literally undeniable gets to be called "properly basic." For I believe we need a reason, at least some reason, to believe anything else--if it could be false, if there is any chance it could be false, then we need some reason to believe it isn't false. It needn't be a weighty or elaborate or air tight reason. Any genuine reason will do. But if we need even a tiny little reason to believe something before we are warranted in believing it, then that belief cannot be called properly basic.
For example, the fact that our thoughts and "interpretations" exist at the moment we experience them is undeniable, regardless of whether they are true or correct, and therefore our belief in the existence of those thoughts and interpretations is properly basic. Likewise, it can also be undeniable that there exists at this moment an experience of our "interpretations" cohering well--or not cohering well--with everything we are experiencing at the same moment. Now, just because we are experiencing an interpretation of the facts that is cohering well with everything else going on, doesn't mean it is cohering well (we could be in error about that), nor does such coherence mean our interpretation is true (since there are often countless explanations of the same facts that are equally coherent). But the fact that we are experiencing that coherence is undeniable. Since it cannot be false that we are experiencing it right here and now, it is properly basic. We get to believe we are having that experience without needing any reason to believe that, other than the one reason entirely contained within itself: the fact that it cannot be false.
The same holds for memories, which are also properly basic. Whether they are true memories or false, or accurate or inaccurate or flawed or precise, none of that is properly basic, but the conclusion that they are true or accurate or precise can be (and ought to be) the deduction from properly basic experiences, which include thoughts and hence "interpretations," as well as other memories, "experiences of coherence" and "experiences of an idea making sense" and so on. These can even include undeniable desires, like an experience of having the desire to follow a certain rule. There is literally nothing else left. When you add up all the reasons (all the reasons) you have right now to believe any x, you will always (always) end up with a finite collection of experiences (whether a combination of perceptions, emotions, thoughts, memories, etc.), which are in turn entirely and without remainder reducible to a finite (not infinite) collection of properly basic, in fact literally undeniable, experiences (again, whether these be perceptions, emotions, thoughts, memories, etc.).
Therefore, every epistemology avoids infinite regress, since there is always a point where the justifying evidence simply stops. You couldn't continue the train of evidence even if you wanted to. Therefore, there is no such thing as infinite regress in epistemology. Which means the only difference between my epistemology and Plantinga's is that he stops with an arbitrarily selected set of deniable evidence, whereas I argue we must keep going until we've gotten to the bottom, which is always a finite set of undeniable experiences. This is all it can ever be, because in the end, there isn't anything else left. I have argued this more clearly and in more specific detail at the Secular Web, in an article I actually cite in Sense and Goodness, which I recommend to everyone interested in natural philosophy: Defending Naturalism as a Worldview: A Rebuttal to Michael Rea's World Without Design (2003).
Memory and Subconscious Reasoning
Third, I do not agree with Chris that we must presume memory is true in order to reason. If that were the case, we could never identify a false or inaccurate memory. Instead, we hypothesize the reliability of our memory, and constantly test that hypothesis against current experience, which includes current experiences of those and other memories, and experiences of coherence among all our presently occurring experiences and memories, and so on. Of course this goes on unconsciously or nonpropositionally most of the time, but the process is the same then as when it is fully cognitive.
As I'll note again below, just because a process of reasoning is unconscious does not mean we believe its conclusions for no reason. Thus, we take for granted that a science textbook tells us the truth about what scientists have observed, but we don't take this for granted for no reason. We have accumulated a great deal of evidence regarding the reliability not only of science textbooks themselves, but of the processes and events that go into producing their contents. Just because we don't reason through all this evidence every time we pick up a science book doesn't mean our trust in that book is properly basic.
Likewise, when we intuit that someone is lying to us, that they are lying is not a properly basic belief. If we can't work out specific reasons why that intuition is valid, we won't be justified in trusting it at all, while if we can work out such reasons, then we're not looking at a properly basic belief. Even when our intuition has become reliable enough that we trust it even without examination, this too we do for a reason, such as the fact that we have a large number of experiences of memories of our intuition's success in relevantly similar cases. That these experiences exist is properly basic, but not what we deduce from them, like that our intuition in such cases is reliable. Thus, we don't have to work out all the steps of reasoning or all the evidence we actually are working from, but we still need all that evidence and reasoning in order to be warranted in believing something. A belief can only be properly basic if we don't have all that evidence and reasoning stashed away in our subconscious, and yet still are warranted in maintaining that belief.
Memory's Role in Reasoning
Fourth, one thing I don't explain in Sense and Goodness is that I believe deductive reason involves simultaneous perception of the major and minor premise (while induction is simply deduction with the major premise being some general inductive principle). So we do not require memory to arrive at a conclusion from premises. We only require a memory to previously store, and thus recall at the present, the premises we are using in our reasoning at any given time. Obviously, many remembered premises are also the conclusions of previous acts of reasoning, but we still don't require memory to reason, only to recall the results of past acts of reasoning. If you want to understand the importance of this simultaneity in reasoning processes, see my lengthy discussion in another article, which was also cited in Sense and Goodness, although it addresses zillions of other issues besides, and is altogether inordinately long and dry: Critical Review of Victor Reppert's Defense of the Argument from Reason (2004), though for the present question, you can skip to the section there on AfUC. Or just forget this obscurity and continue on here.
All Epistemologies Are Fundamentally Normative
Last but not least, another thing I could have included in Sense and Goodness is that all epistemologies are fundamentally built on axioms that are, in fact, imperative propositions. In other words, every epistemology is constructed on top of a set of "I ought to believe x when y" propositions, and therefore, if it is true that any epistemology ought to be adopted by everyone, then epistemology as such is a subset of morality, and it would be immoral to knowingly violate the axioms of a true epistemology. That's another issue (regarding the ethics of belief), but it's important here for one particular reason I did not bring out in Sense and Goodness:
All epistemological arguments end with a set of imperative propositions, not with a lone set of non-normative facts. For example:
- "I ought not to believe x when I have no reason to believe x"
- "I ought to believe x when x coheres with all other current experiences (including experiences of memories, etc.), with less fudging than any alternative I know"
- "I ought to believe the relative probability of x is y when y is (or is as close as I can know to) the actual frequency of x relative to ~x in my experience"
That these principles (and others one could add to the list) are irreducible doesn't mean I can't defend them. It's just that any such defense will ultimately rest on some normative premise, such as "things will go better for me if I follow these principles," which is itself, ultimately, a conclusion based on those same principles. Hence we always end up in some circular argument, a fact even Plantinga admits of his own, and in fact every conceivable epistemology--even God's. Yes, God as well. For even He can never be certain he is not the victim of a Cartesian Demon, or that there isn't some flaw in his knowledge or memory or reasoning. I already articulated this same point about my own worldview, again, in Note 6 of Critical Review of Victor Reppert (2004).
This circularity ends infinite regress, which is why no epistemology really suffers from the problem of regress. How so? Well, remember how there are always two lines of questioning, one about the facts and one about the principles we use to interpret those facts? Okay:
The first line of questioning ends with a full dead stop at some finite set of undeniable experiences. For once you end up with an answer that cannot be false, you can no longer ask, "How do you know it's true?" How do I know? Because it can't be false. It would be nonsensical to then ask, "How do you know that?" For if I said it were false, then I would be saying "this experience exists right now and this experience does not exist right now," which is a meaningless sentence, because it asserts what it also denies, and therefore it describes nothing (see pages 42-43 and 188-91 of Sense and Goodness). Thus, obviously, I cannot fail to know I am having such-and-such an experience right now. To express doubt about this would then be to question not the facts, but the rules I choose to follow when interpreting those facts (in this case, how I choose to define "true" and "false").
Hence we end up with the second line of questioning, about our inductive and deductive principles. But all such lines of questioning end with a circular argument: our principles are true because our principles are true. There is therefore nowhere else to go. This is like Hawking's notion of nutshell cosmology, where there is no first moment of time because as you approach it you eventually just curve back around and end up where you started. In such a case the timeline is not infinite, and yet has no starting point. Because it's circular. So, too, in epistemology: once your only justification for adopting a principle is the principle itself, you can no longer ask, "How do you know that principle is true?" How do I know? Because I observe it to be true. How do I know I observe it to be true? That I am observing it to be true is an undeniable experience. Hence we are back to the first line of questioning, about what I am experiencing, where all questioning ends.
Thus, there is no regress. But the underlying normative nature of this end game must not be overlooked. In effect, my entire epistemology rests on a conjunction of just three premises, which I will greatly oversimplify here:
- A: "Following certain principles will probably make things go better for me than not following them will"
- B: "If I want things to go better for me, I ought to follow the principles that will probably make things go better for me than not following them will"
- C: "I want things to go better for me."
Thus, the buck stops with the evidence, and the evidence is a finite collection of undeniable experiences. Though these undeniable experiences are also compatible with a contrary hypothesis (~A or ~B), the experiences I am having do not entail that contrary hypothesis unless we introduce an intervening premise, such as "a Cartesian Demon has fooled with my memory and is deceiving my senses." Thus, as long as we have no reason to believe any such premise, then we have no reason to believe any hypothesis contrary to A and B. In other words, among the total collection of our undeniable experiences at any given moment, all we have is evidence supporting A and B and none supporting ~A or ~B, which is to say, none supporting any premise that would have to be true in order for ~A or ~B to be true.
Circularity arrives here at the point when we decide on the most fundamental principle underlying all of the above, which I will call principle K:
- K: "I ought to believe x when I have (a) evidence supporting x (or x is undeniable) and (b) no evidence supporting what would have to be true for me to have (a) and yet for x to be false."
- ~K: "I ought to doubt x when I have (a) evidence supporting x (or x is undeniable) and (b) no evidence supporting anything else that would have to be true for me to have (a) and yet for x to be false."
We are thus faced with an ultimate choice: K or ~K? Which principle do I follow? I can try them both out right now, and immediately see that following K leads to correct predictions and the satisfaction of my desires and the fulfillment of my plans, while following ~K does much poorly in all three respects. I can repeat this test endlessly. It still remains that a Cartesian Demon could be meddling with my mind so that I keep falsely experiencing and remembering the good performance of K and the poor performance of ~K, when all the while, unbeknownst to me, ~K has been performing better than K (or equally as well). But as long as any CD keeps doing this, what's the difference between that, and K actually performing well and ~K performing poorly?
Hence my Matrix analogy in Sense and Goodness (p. 32), which Chris singles out: until you allow that there could be some potential difference between the world created for us by a CD and a real world, there is no difference between them that matters. The world created by the CD is a real world: our desires are actually fulfilled, our plans are actually realized, our predictions actually come true, and continue to do so, always and forever (until we're dead). Only if you allow that it might not be "always and forever" does it become meaningful to talk about a difference, because then, and only then, is there a difference that matters. But then we have the possibility of predicting different outcomes for each hypothesis, and so the two hypotheses become testable, which means the CD hypothesis is only ever confirmed when its unique predictions come true. But as long as it remains unconfirmed, we continue to lack any reason to believe that hypothesis--even if (unbeknownst to us) it turns out to be true.
Ultimately, this is a conundrum Plantinga faces every bit as much as I. So pointing out the inevitable circularity of rejecting all Cartesian Demon hypotheses is no objection to my epistemology, since it is equally an objection against all epistemologies, thus forcing us against the rocks of the same dilemma: we simply have to choose how to behave. Will it be in accordance with K, or ~K? We constantly observe, in every waking moment that we bother to test, that the undeniable facts of both our desires and our immediate and present experiences are only satisfied by following K. Therefore it makes no sense to follow ~K, even if it happens to be the case (unbeknownst to us) that ~K is true. So that's where all epistemologies end: "I ought to follow K."
This is not a properly basic belief, because we have a reason to follow K rather than ~K, namely the undeniable fact that we desire things, combined with the undeniable fact that in any moment we put to the test, we will often experience the fulfillment of our desires only when following K, but not when we follow ~K. These two facts do not combine into a deductive proof that K is true, but they do provide a reason to follow K, and as long as we have no reason not to follow K, having a reason to follow K is a sufficient reason to do so. On the other hand, all of those reasons, which are all that justify my embracing the fundamental principle underlying the whole of my epistemology, are undeniable facts, and therefore properly basic. Regress ends.
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Epilogue: Of course this just gets us back to how we choose to define anything as "true." In Sense and Goodness without God (pp. 23-43) I define the "meaning" of any proposition as simply the sum of everything that it predicts, and "truth" as the condition of when that meaning corresponds to that result. In other words, when that which a proposition predicts, is indeed what is experienced. We can then show (by evidence and logic) that the best hypothesis for why a proposition turns out to be true, is that it is describing an actual physical state of the world. Exceptions can be proved as such by evidence (which always reduces to undeniables of experience), which is how we can rule out pragmatism as a viable epistemology: those propositions that generate successful predictions by accident, can be shown to be less reliable than propositions corrected to correspond to actual reality; thus "truth" always reduces to correspondence with reality.
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[Update: There are also Bayesian (mathematically deductive) arguments against all Cartesian Demon hypotheses: see Epistemology without Insurmountable Regress or Fallacious Circularity (2015) and Eight Questions (2018).]
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If, in your epistemology, "only what is literally undeniable gets to be called 'properly basic'", then do you believe that all persons who faithfully adhere to this epistemology/methdology will arrive at the same or (very) similar conclusions? Bertrand Russell believed that many of the *basic* assumptions that we have cannot be proven and there is no logical contradiction in their denial.
ReplyDeleteSince the fact that I cannot deny my PRESENT or IMMEDIATE experiences of or feelings about something doesn't ensure the truth of what I infer and/or the basis of that inference, a set of undeniable experiences can still be the ground of dubious inferences, metaphysical errors and categorical mistakes. Therefore, I don't see how "undeniable experience" (AFTER the moment we experience it) is necessarily epistemologically superior or isn't ultimately identical to "deniable evidence."
Please correct me if I have misunderstood or misconstrued the meaning of your position. I am certainly not defending Plantinga at this point.
ReplyDeleteI have posted my reply here.
ReplyDeleteThis displays vestigial Cartesianism in its approach. How can I justify my belief that X by resorting only to my explicitly and consciously entertained mental states in the chain of justification?
ReplyDeleteWhy not start with the beliefs of other animals? Start like a scientist, with a full suite of beliefs in tow, and try to show how a monkey's or other person's belief can be true. E.g., the monkey believes there is a bananna on the table. We, as scientists, describe the belief-formation systems, which are linked to the perceptual systems of the monkey, which provide highly accurate information about its environment.
None of these processes have to be transparent to the monkey, none of the beliefs have to be consciously derived from consciously entertained premises in their consciousness box. Cognitively impenetrable (to them) processes occur which we scientists know are reliable. (This is called externalism as opposed to internalism in which justifications for beliefs must be other consciously entertained beliefs: externalists ground knowledge in the world-brain relations that we observe as scientists (e.g., the rats I work with have neurons that track the properties of objects that the whiskers contact).)
Also, we can justify our own beliefs about the world because these theories which we developed for other people, animals, nervous systems also apply to us. There is no need to introspect and use our own mental states to justify the claim. Scientists don't justify their beliefs by appeal to their phenomenology, and a naturalistic epistemology should probably conform to this wise trend.
Ultimately someone like me has no answer to the Cartesian skeptic. But luckily, neither does the Cartesian skeptic. And who wants to waste their life trying to prove there is an external world, that we are not dreaming? Unless that sort of thing turns you on, externalism seems the most plausible epistemic approach.
Mr. Jargon: Yes, I believe "that all persons who faithfully adhere" to my epistemology will arrive at the same conclusions, but only (a) about objective matters of fact and (b) when they all make exactly the same observations. If one person sees more than I do or less than I do, or if they see different things than I do, then even following the exact same method they will not necessarily come to the same conclusions. Our beliefs will converge statistically over time, the more we strive to test our beliefs and acquire wider knowledge, but I doubt any two people will ever have exactly the same beliefs about everything, simply because everyone's experience is so different, as is the sphere of knowledge available to each.
ReplyDeleteAs for Bertrand Russell's "basic assumptions" that "cannot be proven" yet "there is no logical contradiction in their denial," I would need specific examples of what you mean. I suspect you are referring to what I call principles, not undeniable facts. The fact that you can deny basic principles without logical contradiction is exactly the point of my blog entry. It can only be said to be impractical to deny them.
Finally, you seem to give an invalid example when you refer to "feelings about something" which don't "ensure the truth of what I infer." You are confusing basic knowledge (that you feel x) with derived knowledge (that x is correct). Read my book's chapter about emotion (pp. 193-208) and intuition (pp. 178-81). Also, I do not claim "undeniable experience is necessarily epistemologically superior to deniable evidence" except in the sense that it is undeniable. All I claim is that a belief system that is built on a foundation of undeniable experiences will be epistemologically superior to a belief system built on a foundation of deniable assumptions (like "God exists" or "Christianity is true" or "I live in the Matrix" or "beans have souls," etc.).
Blue Devil Knight: You cannot immediately assume monkeys even exist, much less have neurons and so forth. You are thus bootstrapping, putting the cart before the horse. Hence the question is: How do you know monkeys exist and have the same brain structures that we do? You can't answer that question by appealing to the existence of monkeys and their neurons. That's the problem Chris asked me to address, and which my blog entry is about.
ReplyDeleteOtherwise, what you might be trying to say is essentially what I said, about not needing a completely thought out justification structure for every belief. I agree with that, in the way I explained in my blog. But monkeys will nevertheless embrace many false beliefs (insofar as they can be said to have beliefs) precisely because they can't think about the justification structure for their beliefs and thus use this knowledge to analyze discrepancies and locate errors.
For example, if I drop my calculator on a monkey by accident, that monkey might form the false belief that I am attacking it. It's inability to distinguish between raw data (I felt something hit me and it looked like it fell from his hand and I am scared and it hurts) and inference (what possible explanations exist for all this raw data and which explanation ought I believe is the true one?) is what I am referring to when I say our beliefs should be rooted in undeniables, not in deniable assumptions. We do not need to work out the roots of every belief in every case, only when challenges or discrepancies appear, and we don't have to shun deniable assumptions, but we need to treat all deniable assumptions as exactly that: deniable assumptions, not as properly basic beliefs.
That's the point of my argument. Thus, that monkeys exist and have similar brain structures as we do is a deniable fact and therefore cannot be a properly basic belief. But we can still believe it, and infer other things from that belief, precisely because we recognize that we have constructed that belief from a vast array of undeniable experiences, and know of no better explanation for that array than that the monkeys exist and have those properties.
In the end, your closing point is almost identical to mine, which I state several times in my book (look up "Cartesian Demon" in the index, and also "Matrix, The").
Regarding Chris Hallquist's Response:
ReplyDeleteMemory: I agree that we must count on memory. I am not saying we should start with a distrust of memory. What I am saying is that we do not (and cannot) simply assume all memories are reliable. That any memory is reliable is a hypothesis that we constantly put to test, just like every other belief. As long as "these memories are reliable" produces no falsifying experiences (no contradictions, discrepancies, confusions, failures, etc.), we are entitled to believe it. But we are entitled to this not because "these memories are reliable" is a properly basic belief. To the contrary, it is a belief based on our experiences of success and coherence and comformity, and a belief we abandon when the data falsify the hypothesis. Indeed, my wife quite frequently proves my memory false! That my memory is reliable cannot therefore be a properly basic belief for me. But since I have no experience to hand of my memory constantly failing me, I have a reason to trust it most of the time. I therefore do not trust it for no reason, and therefore it is not properly basic.
Ontology: "What is the indubitable source of the claim that the coherence of our peceptions (with eachother) is reason to think that they match some external world?" Chris seems still not to have read the articles I directed him to. I answer this question specifically in my critique of Rea, linked in my blog entry. The answer, in short, is that this is the best explanation of the undeniable experiences we have, which explanation is itself among those undeniable experiences. In other words, it is undeniable that this is, so far as I know in any given moment, the best explanation of the remainder of my experiences in that moment.
This does not entail that it is the best explanation, since we don't know everything, and we could be in error about many things. But this is where basic principles enter in: Which ought you believe? Should you believe in what you cannot deny is the best explanation that you know, or should you believe in some other explanation that does not appear to you to be the best explanation? The mere logical possibility that the latter principle could lead you to the truth is not a sufficient reason to embrace that principle. Instead, all your experiences at any moment of testing either principle will frequently demonstrate the success of the first, and the failure of the second. And this brings us back to where my blog entry ends up.
Circularity: "circularity" is "just as problematic as an infinite regress of justifications, and in fact can be seen as such an infinite regress." Wrong. It is not the same because it does not lead to anything but a finite chain of reasons, and a finite chain is not an infinite chain. Perhaps Chris needs to read Plantinga more carefully, since Plantinga already makes this point himself: it is logically impossible for any epistemology to exist that is non-circular at some level of analysis. I though I made that clear myself in my blog entry, yet Chris still doesn't seem to understand this point.
At any rate, if Chris can prove the existence of a completely non-circular epistemology, he ought to publish this in a peer reviewed philosophy journal. It will make him the most famous man in the history of philosophy. Plantinga himself will fall on bended knee. Meanwhile, when I say "we can believe nothing without justification" I am referring to sufficient justification to warrant belief, not absolute deductive certainty, which I have very adamantly denied is possible in all my writings on epistemology, so Chris can have no excuse for supposing otherwise. As long as my beliefs can be (whether they actually are or not) deduced from a combination of undeniable experiences and unabandonable principles, my beliefs are fully justified.
As my blog entry states, undeniable experience is what Chris calls "the incorrigibility of immediate experience," but unabandonable principles refers to the normative principles of belief formation, which derive from the undeniable experiences of what we want. Thus, our principles can be denied (as all principles can), but they cannot be denied in practice, i.e. we could not abandon them without doing substantial harm to our welfare, our interests, and our predictive success. Though it is logically possible that we are wrong about that (hence my discussion of Cartesian Demons), there is no reason to believe we are, while every moment of our experience confirms that we are not. Nothing else is necessary to be justified in our beliefs. We need no other reasons. Therefore, regress ends.
Properly Basic Beliefs: Chris proposes three properly basic beliefs, "That our senses are generally reliable," "that our memory is generally reliable," "that our notions of rational inference are generally reliable." These cannot be properly basic, because we have all experimentally learned them as children, and can easily adduce falsifying conditions for them. Therefore, we believe them for reasons, not for no reason at all. By definition, a properly basic belief is a belief that we need offer no reason to believe. But we do need to offer a reason to believe our memory, senses, and any "notions of rational inference." We would never have adopted the latter otherwise, and would never have learned to trust the former otherwise.
Moreover, we cannot trust them for no reason, precisely because we know they are often incorrect. We often have embraced and later rooted out bad principles of inference, incorrect perceptions, false or inaccurate memories, and so on. That means we need principles to determine when our memories, senses, and rules are reliable and when they are not, and those principles must work on data (since it is only by differences in the data that we can distinguish bad memories from good, bad rules from good, bad perceptions from good, and so on). Therefore, these principles and these data are necessarily more fundamental, and therefore it is these that are properly basic (unless we can identify something even more basic still).
Whatever these principles are, we apply them unconsciously all the time (even though some of us can also consciously articulate them), hence we quickly assess when we think we can trust a rule, or a memory, or a sensation, based on contextual clues (undeniable data) according to fundamental principles (the conscious or unconscious criteria by which we identify signs of untrustworthy data). Therefore, a given memory, perception, or rule is not necessarily basic, but the more fundamental data and rules by which we assess when to trust a memory, perception, or rule, that is basic. You only end up with properly basic data and rules when you no longer need to give a reason to believe that data or those rules. That's what it means to have a set of properly basic beliefs.
Conclusion: Chris concludes "there are no a priori limits on what can be believed without justification." This is a very bad conclusion to reach, for it amounts to epistemological relativism. Anyone gets to believe anything they want, and Chris has no right to tell them they are wrong. I disagree. There are limits on what can be believed without justification. Whether they are a priori or not is irrelevant and not anything I will bother asking. All that matters is that there are limits: there are things you ought not believe for no reason, and there are only a finite number of things you ought to believe for no reason.
The only things you ought to believe for no reason are (a) undeniable experiences and (b) unabandonable principles, the former because you can't deny them, the latter because you can't get on without them. And there is no doubt that (a) and (b) are finite and therefore limited. Since you have not lived forever, even loading up all your memories at once, though it would generate a vast number of experiences, it would not be an infinite number. You have only experienced a finite, albeit large, number of sights, sounds, thoughts, etc. And there are certainly not an infinite number of principles you can't live without. Even if we imagine all the principles we could ever adopt for no reason, which were necessary to successfully predict the future and obtain the fulfillment of our plans and desires, including all the brilliant principles we haven't thought of yet, their number is unlikely to be infinite, especially since most will reduce back to others. Just as all mathematics reduces to just nine axioms, all reason, even for an omniscient being, will undoubtedly also reduce to a finite set of axioms. And even if not, there are still boundaries, still limits, on which axioms get to be included in this set.
Therefore, there are limits to what we can believe without needing a reason to believe, and those limits ought to be heeded. At the same time, this does not mean there is nothing we can believe without needing a reason to. There certainly are such beliefs. Since properly basic beliefs are, by definition, beliefs you can hold without needing a reason to hold them, it is important that we get right what it is we can honestly believe without a reason. Chris, in my opinion, not only has gotten it wrong, but hasn't even suggested any set of facts or principles that would qualify. I cannot use "our senses are generally reliable" as an axiom because that tells me nothing about when my senses aren't reliable or how often or to what extent or in what way, and yet those are the things I need to know. Those are the things that will underly my beliefs and stand as my reasons for believing (or not believing) what I see, think, or recall. Therefore, those are the only things that will have any plausible claim to being properly basic--or whatever it is that underlies them. And that is exactly what I articulate in my original blog entry.
You cannot immediately assume monkeys even exist, much less have neurons and so forth. You are thus bootstrapping, putting the cart before the horse. Hence the question is: How do you know monkeys exist and have the same brain structures that we do? You can't answer that question by appealing to the existence of monkeys and their neurons. That's the problem Chris asked me to address, and which my blog entry is about.
ReplyDeleteI am saying that to accept those as the terms of the debate is to already make too many concessions to a nonnaturalistic, anachronistic, and fruitless epistemological position (pre-Quine and Sellars Cartesian positivism). The slogan I am defending is "There is no first philosophy."
Science does not try to ground itself in experience as you describe it, and if they did we would not have made any scientific progress. Science is in the business of generating theories about the world which acheive the best fit with evidence (where evidence is not taken to be 'internal' experiences but simply more facts about the world: dial positions, voltage values, rat behavior, and the like).
If you look at the origins of our knowledge, concepts about our own experiences are not the starting point. Kids, monkeys, nonphilosophers, scientists, take as their original basis set statements about the world. We see objects, things, with properties (monkeys and dial positions on instruments). Experiences (as you describe them) are abstractions from this primordial world-centered
conceptual framework. I still don't experience experiences, but things in the world, and it us upon this that all my theories, even my theories of experiences, are based (this is the key point of Sellars' seminal Empiricism and the Philosophy of Mind). (Note I am saying 'experiences as you describe them' because I experience things in the world, not my mental states: I experience 3-D things out there, not internal representations).
For example, if I drop my calculator on a monkey by accident, that monkey might form the false belief that I am attacking it. It's inability to distinguish between
raw data (I felt something hit me and it looked like it fell from his hand and I am scared and it hurts) and inference (what possible explanations exist for all this
raw data and which explanation ought I believe is the true one?) is what I am referring to when I say our beliefs should be rooted in undeniables, not in deniable assumptions.
I agree that the ability to reflect on and modify beliefs is an important epistemic skill, and that monkeys have this skill to a lesser degree than adult humans. But this is orthogonal to the claim that we ultimately must root our jusitifications in experience. If the monkey thinks "Something just hit me in the head" (true) and also "Someone is attacking me" (false), if he had language and better reasoning skills, we could explain to him that you accidentally dropped something. It isn't his lack of a basis set in experiences that makes him different, but his inability to express his beliefs and then engage in rational interrogation of those beliefs, that makes him different. He doesn't need to make a distinction between appearance and reality to get this: he needs to be able to be more intelligent in his reasoning about the world.
Ultimately, this desire to ground science in some epistemically priviledged class of experiences is quixotic. The naturalist in epistemology realizes that even his epistemic theories are subject to revision, not immune to error, and to hope for any kind of immunity (as shown by the claim that the monkey can be wrong, as if that damns the whole epistemic enterprise) is to misstep into Cartesianism. We don't have that in any science, why impose that on your epistemology?
That's the point of my argument. Thus, that monkeys exist and have similar brain structures as we do is a deniable fact and therefore cannot be a properly basic belief. But we can still believe it, and infer other things from that belief, precisely because we recognize that we have constructed that belief from a vast array of undeniable experiences, and know of no better explanation for that array than that the monkeys exist and have those properties.
This is again a throwback to positivistic phenomenalism (which Carnap tried to implement in his book The Logical Structure of the World). There are many
problems with this. For one, are the logical operations which you use to generate this supposed 'construction' of the world, part of your experience? If not, how can
you get past mere naval-staring, making a bunch of claims about your experience? More importantly, is the claim that propositions about experiences are more epistemically secure than claims about things in the world itself based on indubitable experience? Also, what if scientists had no sense experience, but acted just the same way they do now (e.g., a bunch of Chalmers' zombies). We would still be able to evaluate their science as good or bad. So experience seems to be neither necessary nor sufficient for good science.
Finally, as a theory of how science works, it is empirically false. A good naturalistic epistemology needs to be more sensitive to the empirical details of the scientific enterprise.
In sum, while I take there to be a real distinction between theory and evidence, and the latter to be claims that we have no good reason to doubt, this is not the same as the distinction between 'claims about experience' and 'other claims.' The picture of knowledge somehow resting on a foundation of claims about experience, while seductive, is just an empirically inaccurate portrayal of knowledge. Perhaps you are making a normative claim about how things should work, but it isn't
how things do work.
Note: the locus classicus of the position I am pushing, besides Sellars, is Quine's Two Dogmas of Empiricism.
Science starts and ends with the world, and fits the mind therein. The converse Cartesian view just gets it backwards, as does the corresponding epistemology.
I may try to get in a fuller response later, but I'm currently in the middle of the run-up to final exams here in Madison, so let me just deal with one key issue: circularity. I do not claim to have found a non-circular epistemology. Nor am I reading Carrier as to say we need absolute deductive certainty to believe anything. The fact that he's merely demanding some kind of justification is problematic enough. The reason is that not only to circular arguments not provide an absolute deductive justification, they do not, as a rule, provide any sort of justification at all. Therefore, if as Carrier says all epistemologies are circular, then he cannot meet his own requirement that, "we can believe nothing without justification."
ReplyDeleteBDK:
ReplyDeleteBy the time we're doing philosophy, we've already learned language and concepts, and have had many perceptual experiences and formed memories of them. The externalist, naturalized epistemological perspective is to ask whether the processes by which we've accumulated that information and the methods which we use in belief formation and revision are reliable, and to try to answer that question through mechanisms such as scientific investigation. The internalist perspective is to try to construct an edifice of justification without appeal to anything other than our own beliefs and experiences, either based on a foundationalist or coherentist structure. The latter seems to me a lot more likely to fail.
Lippard: I agree. The view that we can't use results of scientific investigation in our epistemology is a throwback. The attitude that we need a first philosophy, an epistemology that doesn't resort to any scientific facts, because it must ultimately ground those facts, is a seduction that should be sidestepped like a pile of horse#%@* by the naturalist.
ReplyDeleteBlue Devil Knight: The slogan I am defending is "There is no first philosophy."
ReplyDeleteI agree with you (and make exactly that point in my book). I am not talking about first philosophy (unless you mean something unconventional by that phrase). I am simply talking about foundationalist epistemology. That counts as "first" only in order of analysis, but not "first" in the sense of a priori. All a priori truths must be analytically, hence necessarily, true. To the contrary, I am talking about truths that can only be synthetically, hence only ever (and only at best) probably true. That is not first philosophy.
To be justified in believing that monkeys have brains like ours, we must be be able to give reasons to believe that, and those reasons must be sufficient to warrant our believing it. It wouldn't be a scientific claim otherwise. In contrast, you can only use "monkeys have brains like ours" as a reason to believe "monkeys have brains like ours" if "monkeys have brains like ours" is a properly basic belief. It is not. Therefore, though "monkeys have brains like ours" is a hypothesis of great value in understanding many issues in epistemology (I never said it wasn't), it is not a foundational datum of epistemology and thus it is not relevant to the present discussion, which concerns only what beliefs we can maintain without needing any reason to (apart from themselves).
Hence when you say "science does not try to ground itself in experience as you describe it" you seem to be confused. I'm talking about philosophy, not science. Science rests on the foundations provided by philosophy, including epistemology. As you imply, scientists take all these foundational issues for granted. But are they justified in doing so? That question is answered in the affirmative by (most) philosophers. How it is that we come to that affirmative answer is (part of) the subject of my blog entry.
So please don't jump to a completely different level of analysis. Since I am not describing "a theory of how science works" I don't fathom what you mean by claiming my discussion of properly basic beliefs "is empirically false." You seem to be imagining that I discuss nothing else about epistemology or scientific practice in my book. To the contrary, I discuss a great deal more. I completely agree that "a good naturalistic epistemology needs to be sensitive to the empirical details of the scientific enterprise" and that it must employ data from the sciences. And you will find exactly that in my book. So please read my book before adding any more comments.
On the matter of epistemology, you note that "if you look at the origins of our knowledge, concepts about our own experiences are not the starting point." Indeed. That's the very thing I state in my book. Contrary to Plantinga's claim, naturalist epistemology does not start with propositions (articulated concepts). It starts, ultimately, with raw, uninterpreted experience, and intuitive principles of judgment. From that beginning, as children interacting with the environment, we automatically build up a system of trusted and distrusted hypotheses (not only about what is and why, but also about the principles of judgment we should or should not accept and when). This system of implicit hypotheses forms the foundation of our philosophical worldview, which includes an epistemology, a metaphysics, an ethics, even a politics, though rarely is any of this consciously analyzed or well-thought-out. I discuss this point, too, in greater detail in my book, where you will also find that my discussion of language and reason and abstractions agrees entirely with you.
So when you ask "are the logical operations which you use to generate this supposed 'construction' of the world, part of your experience" you need to read my book (where I answer that question specifically) and then read more carefully my blog entry, which expands my book's discussion by elaborating on only those logical operations that are properly basic, i.e. the few that we don't need a reason to believe are reliable.
By definition, all scientific facts need a reason to believe them--that is exactly what science is about: accumulating reasons to believe its findings and conclusions (like "monkeys have brains like ours"). For both scientific findings and most basic logical rules, we need reasons to adopt them, just as we have reasons for abandoning other (bad) principles of judgment, and modifying yet others. The process of learning logic, and unlearning fallacies, is a process of accumulating evidence regarding which principles to trust and which not, just as the process of science is a process of accumulating evidence regarding which claims to trust and which not.
But we have to start somewhere. There has to be some ultimate principle (or set of principles) by which we ascertain which principles to trust and which not, and we will never be sure we are relying on a sound fundamental principle until we check. That's what philosophy is for. Likewise, scientists must start with some data that precede the science they are about to do, and ultimately that data is experience.
Hence whatever our fundamental principle of judgment is, by which we judge what other principles to trust (like, "Should I trust science?"), the philosopher is posed the question, "Why should we have adopted that principle?" That's what Chris is talking about. Either we are stuck having to give an infinitely long list of principles, each justifying our acceptance of the next (Plantinga's complaint), or we have to stop with some fundamental principle (or set of principles) that is self-justifying or otherwise needs no further reason for us to trust it.
This is necessarily the case. Therefore, you are forced to choose which camp you are in: the infinite reasons camp, or the "buck stops here" camp. Once you realize only the latter camp makes sense to be in, you will be left with the question, "Okay, so where does the buck stop? And why there?" That's what my blog entry is about. And answering questions like that is what we call "philosophy."
I don't understand your other objections.
I don't just "make a bunch of claims about my experience" and "the claim that propositions about experiences are more epistemically secure than claims about things in the world" is "based on indubitable experience" only in a sense that makes it, in turn, dubitable. As to what experiences imply (but do not entail) that conclusion, and others, read my book.
As for "scientists who had no sense experience, but acted just the same way they do now (e.g., a bunch of Chalmers' zombies)," I honestly can't imagine how that would be possible without data or design, and the former is just another word for "experience" (even if minus qualia) while the latter just pushes back the problem to who (or what) designed these automata and how--if not with data. This links into Plantinga's evolutionary argument against naturalism, about which, again, you can read in my book. Otherwise "we would still be able to evaluate their science as good or bad" is true only if we had sufficient data to do so, and data is experience (even if it ends up being experience without qualia, though I doubt that is really so intelligible as philosophers are fond of pretending). So I don't see how you can claim "experience seems to be neither necessary nor sufficient for good science." That makes no sense to me.
Finally, regarding Quine's "Two Dogmas of Empiricism," the argument of that paper was already refuted by the second edition of Ayer's Language, Truth, and Logic. I am not a positivist, and have much fault to find with Ayer's philosophy, but on the debate between him and Quine, Ayer on balance won, though philosophers today seem unaware of this (mostly because they haven't actually read LTL or "Two Dogmas," or did so carelessly).
But one point on which Quine prevails is exactly here: he asked Ayer for what justifies Ayer's fundamental positivist criterion, and Ayer never provided a satisfactory answer (IMO, because positivism as such cannot produce an answer, and on that score Quine was right, though he was wrong about a great deal else). Hence in my book I answer Quine's best question, and thus, IMO, improve upon Ayer--though by going in a direction Ayer would not have approved (and which cannot properly be called positivist, at least in Ayer's sense). But again, you will have to read my book for that.
Foundationalist philosophy is exactly what I meant by a "first philosophy."
ReplyDeleteI think the possibility of zombie scientists refutes what you are saying. More generally, I don't think semantic ascription ('means', 'is true', 'implies that') assumes that the ascribee has any internal conscious experiences. They could be 'zombies' with no experience, but internal information bearing states that are used to guide their behavior wrt the world. I.e., representations. Perhaps this is all you mean by 'experience' (though I don't experience representations but the world, via representations).
BTW, the philosphers I know don't think Quine killed the analytic synthetic distinction, but that his critique of foundationalism/phenomenalism and his wider vision of naturalism has remained and is roughly right. Sellars is even better (Paul Churchland was Sellars' student, for instance).
The foundationalists nowadays are almost all antinaturalists. I don't think that is a coincidence. Frankly, it is strange arguing with a fellow naturalist about this, as I have never met a naturalist foundationalist (and I have talked to a lot of philosophers).
I'll take a look at your book and give you a more proper response when I get a chance. I have never been totally satisfied with the rather strong antifoundationalist dogma prevalent today: there is something true about foundationalism (namely, that it is via our sensory organs that the world slips into our minds, and it is the fact that science lets the information from those organs dominate its thinking which makes science uniquely good at explaining and understanding the world). I hate the way you describe it, but I think you are hitting on some truths, buried in the Cartesian detritus.
Blue Devil Knight: Foundationalist philosophy is exactly what I meant by a "first philosophy."
ReplyDeleteThat's your own odd definition then, not what the phrase "first philosophy" ordinarily means. And as for what I mean by foundationalism, since I am noty always sure you mean the same thing, see Foundationalism.
Blue Devil Knight: I think the possibility of zombie scientists refutes what you are saying.
I don't believe they are possible. But even if they are possible, indeed even if there actually were such beings, epistemology remains the same--they just do it without qualia. Foundationalism is foundationalism, whether with or without qualia, the structure is the same. Only the details differ, just as the details of my visual experience differ from someone who is color blind: this difference is irrelevant to the question of foundationalism, just as there is no relevant difference between a qualia-based or a data-based foundation.
Blue Devil Knight: Quine's...critique of foundationalism/phenomenalism and his wider vision of naturalism has remained and is roughly right. Sellars is even better (Paul Churchland was Sellars' student, for instance).
I disagree. But that's a whole other issue. As for what I find wrong (and right) with the Churchlands, see Giving the Churchlands a Fairer Shake.
Blue Devil Knight: The foundationalists nowadays are almost all antinaturalists.
I do not believe that is correct. The only anti-foundationalists of note anymore are the reformed epistemologists, who are all Christians. In fact I can't name any real naturalist who is an anti-foundationalist. All are foundationalists of some variety (Kim, Bunge, Boyd, Haack, etc.).
For instance, Quine was not a metaphysical naturalist, since he rejected metaphysics, hence he called himself a naturalist only by perverting what the word normally means. Or, if you prefer I treat his word games more charitably, Quine means something by "naturalist" that is completely different from what I (and most Christians) mean by the word "naturalist." See my extensive discussion of this confusion in Defending Naturalism as a Worldview.
Blue Devil Knight: Frankly, it is strange arguing with a fellow naturalist about this, as I have never met a naturalist foundationalist (and I have talked to a lot of philosophers).
Please name the published philosophers who are metaphysical naturalists but not foundationalists of any sort. I have never heard of such a creature.
Blue Devil Knight: There is something true about foundationalism (namely, that it is via our sensory organs that the world slips into our minds, and it is the fact that science lets the information from those organs dominate its thinking which makes science uniquely good at explaining and understanding the world). I hate the way you describe it, but I think you are hitting on some truths, buried in the Cartesian detritus.
Oh, please don't confuse me with a Cartesian! Cartesianism is an explanandum, not an explanans. It is how things look to the average Joe, which is a phenomenon that brain science now explains (if not yet entirely, it has gotten pretty far and is still proceeding) by showing that Cartesianism is an "illusion" produced by the brain, albeit a useful illusion.
Also, don't confuse what I am saying with "it is via our sensory organs that the world slips into our minds." I disagree with that statement because it excludes entire domains of experience (thought, emotion, memory, etc.) which are not a priori categorically distinct from other domains of experience. Although the thoughts, emotions, memories, etc., that (or so we believe) provide data about "the world" outside our brain do so ultimately through some chain of causation that passes through some sensory organs, one should still not confuse sensory data with mental data.
Moreover, our brain is a part of the world, so the dichotomy between brain and world must be kept distinct from the dichotomy between the world and the mind, since by the law of excluded middle, the brain goes with the world in the latter dichotomy, and therefore all thoughts, emotions, memories, etc. provide our "minds" (in the naive Cartesian sense) with data about the world, even when that data is not entirely traced through sensory organs.
Although, as I explain in my book, our brain is a sensory organ, which detects things about its own states and operations, and the claim that this is so (that there is a brain with states and operations being detected and that thoughts, emotions, memories, etc., are our evidence of this) is a claim that there is a world outside our "mind" (again in the naive, or prima facie Cartesian sense), a world that at the very least consists of a brain.
Finally, don't mistake me for engaging in a priori reasoning in setting up my epistemology. There is nothing classical about my foundationalism. All I am doing is collecting data. What is the sum of all the sound and valid reasons that I have any access to, for believing anything and everything? That sum is finite. Once I've collected the entire set of data, I look at what's in that set, and I find there are only two things there: (a) irreducible, uninterpreted experiences (qualia-events) and (b) practical rules of inference from those (which have no further non-circular justification, but need no further non-circular justification). Both can be reduced no further, and their existence is undeniable, as is the fact that we base our beliefs on them. Therefore, my epistemology is properly foundationalist, but not classically foundationalist.
For foundationalism to be false, one must show me that there exists (c) a sound and valid reason necessary or sufficient to believe something (anything) that is neither (a) nor (b). So long as I have no reason to believe in the existence of any (c), foundationalism is necessarily true. This is not an a priori conclusion because there could still in principle be some (c), as yet unknown to me. I simply have no reason to believe in any (c). Of course, merely presenting a (c) would not be sufficient, since if (c) turns out to be something irreducible that needs no justification, then all we have is another form of foundationalism. Hence I find it extremely difficult to imagine any (c) that would actually refute foundationalism, but since my imagination is limited and fallible, that's as far as I can go.
If there is any alleged (c) that entails non-foundationalism, then let's call that (d). In practice, as far as I have seen, every anti-foundationalist epistemology that proposes a (d) actually fails to propose a proper (c) since their (d) is actually either just another (a) or (b) or, in fact, is not a valid or sound reason to believe anything. Yet a (c) only exists when it is a sound and valid reason necessary or sufficient to believe something, which is neither an (a) nor a (b) nor anything equally foundational.
For example, coherentism proposes a (d) whereby coherency is (at least sometimes) sufficient to believe, but that is not a sound or valid principle (since even coherentists are forced to agree that coherency alone is not highly truth-selective). Although coherency is necessary to believe (in the sense that incoherency is highly falsifying), this is not a (c) but an element of (b), or reducible to some (b), and therefore already an element of foundationalism. Thus, coherentism is only an alternative to foundationalism if coherency alone is at least sometimes sufficient to warrant belief. But all attempts to argue it is fail to persuade me.
Indeed, it seems to me a coherentist must argue that his coherency-inference is basic and therefore needs no justification, which actually makes his epistemology just another form of foundationalism, albeit a bad one. If a coherentist doesn't argue this, then what reason does he have to believe coherentism is true? Hence I suspect there is no defensible epistemology that is not foundationalist, at least in its fundamental structure. Were I a positivist I would declare this an analytic truth, but since I cannot be certain that this apparent impossibility of a defensible antifoundationalism is a genuine impossibility, the most I can say is that I cannot at present imagine one.
I find all the same follows for Plantinga's CT alternative to foundationalism, which resembles a specialized coherentist epistemology of a rather convoluted type.
"...I cannot fail to know I am having such-and-such an experience..."
ReplyDeleteYes you can, because you experience things via your senses, and you cannot be sure of the trustworthiness of your senses except by querying those senses, which is question-begging.
Aq1x: You are making a terminological error. Experiences are the events of perception, not the acts of sensation. That my experiences are caused by senses is an inference (and thus can be wrong), but that I am having those experiences (regardless of what is causing them) is undeniable.
ReplyDeleteThus, I am not talking about the "trustworthiness of my senses," but the deniability of my experiences. Even if all my senses were 100% unreliable (in fact, even if I had no senses at all and my belief that I do is entirely false), I still "cannot fail to know I am having such-and-such an experience" when in fact I am having that experience. What that experience means (as far as whether I have senses that are causing it and whether there is an external world that is affecting those senses and what the structure of that world is, and so on) is a completely separate matter, of what we do with (infer from) the undeniable experiences we have.
But just so you don't make the second mistake, "experiences" are not limited to sensory-caused experiences. Thoughts, emotions, dreams, intuitions, etc., are all experiences, too (and again, our belief that these are differently caused than sensory experiences is a deniable inference, but the fact that we are having all these kinds of experiences is not).