Specter of Reason

This is the second email I just sent to Stevan Harnad. ( See here for an explanation .) Hello again, Here is the rest of my response. It includes a response to earlier points about Descartes and skepticism, as well as a couple of points about categorization and definitions. SH: " the category in question is color, not difference in color or shape." I don't see a difference here. Categories are based upon differences. The category of "color" implies perceived differences in color, or else it is meaningless. SH: “People no more need a definition of feeling than they need a definition of green.” On the one hand, you say an ostensive definition is sufficient. On the other hand, you say that no definition is necessary. Isn't that inconsistent? Some kind of definition is necessary. And people can define green. The category “green” is complemented by other colors. We can ostend green. You cannot provide an ostensive definition for what you mean by ...

Stevan Harnad is an accomplished professor, having founded and edited a respected academic journal, Behavioral And Brain Sciences . He is not a professional philosopher, but he has published articles related to cognitive science and he has a lot to say about feelings and consciousness. I've been engaging him in a discussion at the PhilPapers forum devoted to the explanatory gap . We've touched on side issues related to Descartes, skepticism, and categorization. I am continuing our discussion by email for now, at David Chalmers' suggestion. The following is the first of two emails I just sent Stevan. (The second email can be found here: "Discussion with Stevan Harnad, continued" .) Stevan, David Chalmers has suggested that I take our discussion to email. I hope you do not mind. More and more of my point-by-point responses to you have been rejected by the editorial board (i.e., Chalmers) on the grounds that they are too long and too detailed to be of gene...

“It may easily look as if every doubt merely revealed an existing gap in the foundations; so that secure understanding is only possible if we first doubt everything that can be doubted, and then removed all these doubts.” --Ludwig Wittgenstein , Philosophical Investigations , section 87 I. I think, therefore I am Descartes' famous principle, cogito ergo sum ("I think, therefore I am," also known simply as the cogito ), is probably the most widely known philosophical statement, and it is often considered to exemplify the only thing one can know for certain: that one exists. The cogito might be considered an instance of modus ponens : "If I am thinking, then I exist; I am thinking, therefore I exist." However, Jaako Hintikka ( 1962 ) compellingly argues that Descartes' cogito ergo sum is not a logical inference at all, but a performative act: that a certain cognitive act instantiates direct knowledge of one's existence--that the act of thinking make...

"a nothing would serve just as well as a something about which nothing could be said." --Ludwig Wittgenstein, Philosophical Investigations , section 304 One of the common arguments against atheism is that it offers no ground for morality. Atheism is equated with moral relativism and nihilism, with the idea that nothing is ultimately good or bad, and so there can be no reason to choose one action over another. This, it is said, undermines the very fabric of civilization. I shall argue that this is not only false, but backwards. If there can be any ground for moral decisions, it certainly is not theism. Theism fails to offer a knowable ground for moral wisdom. (Note: This is not to say that religions have no moral wisdom to offer. If a religious institution has moral wisdom to offer, it does so in spite of and in contradiction with its theistic foundations.) Theism may here be defined as any belief in a supernatural agent; that is, any belief which regards natural entit...

This is the latest in my email correspondence with Professor Torin Alter, who specializes in the philosophy of mind. Dear Torin, I'm not going to respond to all of the issues raised in our previous exchanges. I would, for example, like to discuss the issue of operational definitions and your discomfort with my a priori approach to physicalism. But I'll put those topics off for a possible future time. For now, I've decided to construct a new argument about phenomenal knowledge which may help clear a path towards mutual understanding. I checked out your paper, “ Phenomenal Knowledge Without Experience ,” as you suggested, and I would like to begin by quoting its opening sentences: “Phenomenal knowledge usually comes from experience. For example, I know what it’s like to see red because I have done so.” The meaning of the phrase "phenomenal knowledge" is not obvious, which may be one reason why so many papers are written about it. One thing seems clear enough to...

The following is a slightly improved version of a post I recently contributed to the PhilPapers discussion forum . It is a response to Alvin Plantinga's "Evolutionary Argument Against Naturalism ." I do not know how much serious discussion among professional philosophers has been devoted to Plantinga's argument, though I know it is widely heralded by many non-professionals who do not like evolutionary theory. Plantinga wants to use evolutionary theory to attack naturalism, but his argument fails on epistemological grounds. His error is two-fold. First, he fails to state his general epistemological position, and so leaves us wondering what he means by "truth." Second, and more detrimental to his argument, he fails to consider the possibility of epistemological behaviorism, which I take to be the most robust and compelling approach to epistemology (following the work of Peirce, Dewey, Wittgenstein, Quine, Davidson, and Rorty, to name but a few). Consider ...

I'm grateful to a mysterious Steve who, in responding to my last entry, nudged me towards expounding upon a simple idea: that our capacity for speculation far exceeds our ability to make sense; and the corollary, that nonsense is the necessary surplus of scientific discovery. I hadn't spent much time trying to formulate an argument for this idea, but thanks to Steve's questioning, I've begun to forge a philosophical investigation out of it. A key point here is the notion of nonsense, which Steve called me on in his most recent response. He wrote: I guess it comes down to being clear about the meaning of "nonsense". The Phlogiston theory turned out to be false - but until the experiments were done it was a reasonable speculation - it didn't contradict known experimental results, so I wouldn't classify it as nonsense then. To base a new theory on it now - after phlogiston has been experimentally discredited - that would count as nonsense. So, I don...