I'm going to comment on Ryan's latest post:
To set the stage, by using the Cartesian demon I'm playing devil's advocate. For the sake of argument, I'm assuming a far more skeptical viewpoint than I myself endorse. But I'm doing that because I'm responding to Scripturalists on their own grounds.
Mind you, I don't mention the Cartesian demon purely for the sake of argument. Thought-experiments like that demonstrate the limitations of proof. But that's only a problem if we equate knowledge with proof.
I deploy the Cartesian demon as a limiting case to illustrate the consequences of defining knowledge too restrictively. In my experience, Scripturalists draw invidious comparisons between Scripturalism and the alternatives (e.g. empiricism, evidentialism, natural theology, Reformed Epistemology, Van Tilian presuppositionalism, Bayesian probability theory).
For them, to count as knowledge, belief must include second-order knowledge. You don't know something unless you know how you know it. They equate knowledge with certainty and proof.
Indeed, you don't really know anything unless you can define knowledge. Unless you have a full-blown theory of knowledge in your back pocket.
Likewise, unless a process yields true beliefs 100% of the time, that process is deemed to be untrustworthy. That process only yields unjustified opinion rather than knowledge.
That's my target. To a great extent I think Ryan's argument is less with me than his fellow Scripturalists.
I agree with Steve here no matter which contemporary definition of “knowledge” is being used. Whether “knowledge” refers to “true beliefs,” “externally justified beliefs,” or “internally justified beliefs,” there is no need to disprove or falsify a Cartesian demon to “know” something. In the first place, proof or falsification pertains to internalist justification. And even on internalism – whether fallibilist or infallibilist – proof and falsification per se aren’t requirements for knowledge, let alone with reference to something like a Cartesian demon. Not all knowledge is inferentially justified, and not all inferentially justified beliefs need be thought of as the result of deductive reasoning. A Cartesian demon hypothesis needn’t cast doubt on knowledge; it just depends on what one’s theory of knowledge is. I don’t think it’s just my modified epistemology that can avoid this “distinctive problem.” It seems to me garden-variety Scripturalism can avoid it as well.
I appreciate the concession, but in my experience, that's not garden-variety Scripturalism. Not even close. Unless Scripturalism can falsify the Cartesian demon, how can they prove that most of what they deem to be knowledge isn't delusive belief? How can they be certain? How do they know there's no Cartesian deceiver who's messing with their minds? Unless they can rule that out, precious little of what they believe rises to the level of the indubitable or indisputable. And if they can't, how is their position any signal improvement over the alternatives which they disdain? To say they that know it even though they don't know how that's the case is quite a comedown from the Scripturalism I'm acquainted with–past and present.
Where disproving a Cartesian demon would be more relevant is in the realm of apologetics. It’s one thing for me to know there is no Cartesian demon, it’s another to be able to show to someone else how I can rule that out. Do I need to be able to show there is no Cartesian demon to know it? No. But if I can show it, and if I can further make arguments which select for theism in general and Christianity in particular, that’s beneficial. There’s use for that. And in any case, while there are limits to what we can show, this only exhibits the limitations of apologetics, not knowledge.
Scripturalism is a theory of knowledge. More specifically, I’ve argued it ought to be formulated as a theory about a specific kind of knowledge: “any knowledge which is both internally justified and infallible must be founded on divine revelation which, in our case, is coextensive with Scripture” (link). With reference to apologetics, however (which I view as a more pragmatic enterprise), Scripturalists should feel free to utilize all sorts of arguments, not merely those which would constrain all knowledge to refer to internally and infallibly justified beliefs. Frankly, I admit many Scripturalists seem to be a ways off from understanding that.
For starters, a hypothesis of “deception” necessitates a distinction between truth and error. There is something about which we are being deceived; that is, we are deceived into erroneous rather than true beliefs. This idea in turn necessitates certain categories of logic and language. What is truth such that we can be said to be deceived with respect to it? This line of thought leads to further interesting questions. “Deception” also necessitates there being at least one thinking entity, and in the case of the Cartesian demon, two.
Steve at least in principle agrees TAGs are good (link). The initial point, then, is that the Cartesian demon cannot be as omnipotent as many skeptics would frame it. There are some things about which a Cartesian demon can’t deceive us. But then is the Cartesian demon the same as the sort Descartes had in mind? In his outlining of the hypothesis, Steve similarly notes: “[The deceiver] needn't be omniscient or omnipotent. A fallible deceiver could be the source of fallible beliefs, if our beliefs are dependent on that erratic source.”
Okay, but if there are necessary truths which we can recognize as such and show others, then in what sense is this sort of Cartesian demon a problem? We would seem to have internally and infallible justified beliefs after all.
i) Short answer: yes, I think I am discussing the same thought-experiment that Descartes proposed. For instance:
Many readers of Descartes assume that the Evil Genius Doubt draws its sceptical force from the “utmost power” attributed to the deceiver. This is to misunderstand Descartes. He contends that an equally powerful doubt may be generated on the opposite supposition — namely, the supposition that I am not the creature of an all-powerful being:Perhaps there may be some who would prefer to deny the existence of so powerful a God rather than believe that everything else is uncertain. … yet since deception and error seem to be imperfections, the less powerful they make my original cause, the more likely it is that I am so imperfect as to be deceived all the time. (Med. 1, AT 7:21).Descartes makes essentially the same point in a parallel passage of the Principles:[W]e have been told that there is an omnipotent God who created us. Now we do not know whether he may have wished to make us beings of the sort who are always deceived even in those matters which seem to us supremely evident … We may of course suppose that our existence derives not from a supremely powerful God but either from ourselves or from some other source; but in that case, the less powerful we make the author of our coming into being, the more likely it will be that we are so imperfect as to be deceived all the time. (Prin. 1:5, AT 8a:6)http://plato.stanford.edu/entries/descartes-epistemology/#3.2
ii) Ryan in countering something I already granted in my initial reply. I didn't suggest that if the Cartesian deceiver exists, then everything we believe is false. You can still salvage bits and pieces of knowledge even on that scenario.
a) But this goes to a familiar problem. Scripturalism is a form of foundationalism. It views knowledge as an axiomatic system. You isolate and identify certain indubitable, irrefragable truths. You then draw logical inferences on the basis of these first truths. You relate them to other truths in a system of mutual entailments.
Problem is, the data-base for indubitable, indisputable truths is very thin. Abstract "laws of logic." Abstract mathematical formulas. Self-presenting states like "I feel pain." Psychology and modal metaphysics.
You can't extract Christian theology from that data-base. You can't extract Bible history from that data base. It doesn't yield contingent truths. Yet that eliminates the concrete created order.
b) Even the Cogito is essentially confined to the specious present. So long as I'm awake, I know that I exist. But I can't disprove the suspicion that I came into existence 5 minutes ago, or that I will cease to exist 5 minutes from now.
c) In addition, a person whose cognitive faculties are impaired can have a very distorted perception of logic or self-identity. For instance, things may seem logical in a dream that are clearly illogical once we awaken and reflect on the dream.
Naturally, this would be limited to a subset of our beliefs, and being able to show which of these beliefs qualify may further depend on a TAG or TAGs showing that it would be inconsistent to deny, say, a good, omniscient, self-authenticating communicator, but I think this is possible (link, link, link).
I think TAGs are worth developing. But I don't think Ryan developed his TAGs with a view to the Cartesian deceiver. Given the Cartesian deceiver hypothesis, how does he demonstrate the existence of a good God? Our understanding of divine benevolence is based on historical revelation and providence. Empirical contingencies. But that's very different from abstractions like the laws of logic and pure math, or mental states. Likewise, given the Cartesian deceiver hypothesis, the only communication is interior monologue.
Now, Cartesian skeptics could reply that the demon could be deceiving us as to the necessity of all of these conclusions. But skeptics can say or ask a lot of things. Who cares?
I agree. But I'm not a Scripturalist. Given how high Scripturalists set the bar for knowledge, and how they disdain the alternatives, they must take this thought-experiment seriously. The Cartesian demon is the radical counterpart to their radical epistemology.
I'm not trying to saddle Ryan with what other Scripturalists believe. I appreciate his reasonableness. But he ends up with a highly qualified claim that shares the intellectual modesty of rival claims, viz. natural theology, Reformed Epistemology, Bayesian probability theory.
Cartesian skeptics want to get away with climbing the ladder they hope to throw over. They can’t even ask questions without contradicting methodological doubt.
Cartesian skepticism isn't synonymous with global skepticism. Global skepticism is self-refuting. But you can't get much mileage out of that. Although it doesn't take much to refute global skepticism, the exercise doesn't leave you with much to build on. It simply eliminates the utmost extreme.
Our senses were designed to be secondary causes by which we form true beliefs. This causative process isn't arbitrary. It's not as if any old belief would normally be caused by a given sensation. Rather, sensations themselves are the product of interaction with our surrounding environment. That stimulus and our physical, divinely-created processing equipment yield non-arbitrary beliefs.
I like that description. I wish Ryan success in convincing other Scripturalists.
I’m not sure what else “godlike conditions” could refer to.
The conditions that Scripturalists typically stipulate as prerequisites for knowledge.
Furthermore, I think there’s a relevant disanalogy between the fallibility of sensation and the fallibility of reason and memory...To expand on this, how is it that our reasoning and memory could be, in every case, fallible? I can see how we could have two different sense experiences, or how we could have a different sense experience from someone else, which yield contradictory beliefs and therefore leave us unable to ascertain which of the two beliefs is true.
But I don’t see how this could apply to reason or memory across the board. If any beliefs we have are in some sense memorial insofar as our thoughts either reference memories or themselves occur over a span of time rather than an instant, and if our thoughts in every case depend on our implicitly, if not explicitly, following certain logical structures, then I think there is a path to internally and infallibly justified beliefs which isn’t logically founded on sense knowledge.
Once again, I appreciate Ryan's reasonableness, but that's the polar opposite of how Scripturalists (in my experience) frame the issue. For them, a fundamental problem with sensory perception is not that it's misleading in every instance, but that it fails to be dependable in every instance. For them, sensory perception is unreliable unless it's uniformly reliable. By the same token, reason and memory can't be trusted, not because they are uniformly unreliable, but because they fail to be uniformly reliable.
The implicit objection seems to be that if a process yields the right result most of the time, but yields the wrong result on other occasions, then how can you tell which is which? The process itself can't distinguish true results from false results.
Ryan is welcome to take issue with where his fellow Scripturalists characteristically assign the burden of proof. He's reversing the onus. When the dust settles, I don't see that Ryan's position is different in kind from non-Scripturalist alternatives. Rather, it seems to be an eclectic synthesis of the best that the alternative positions have to offer. I don't say that as a criticism. I'm not the audience he needs to persuade. Perhaps he'll have more success with the up-and-coming generation of Scripturalists.