Skip to main content

Three Worlds

Bill Vacellia's exchange with Kevin, on the mertis of dualism vs. materialism when talking about the mind, continues to be of interest. In fact, I think Bill is begining to get in stride because this is terrific:
Suppose we consider an analogy. Distinguished philosophers have proposed that there are three categories of entity. Following Karl Popper, who builds on the work of Gottlob Frege, we can call them World 1, World 2 and World 3 entities. World 1 includes physical items; World 2 mental items; World 3 'abstract' or 'ideal' items. 'Abstract' is not the best term since it suggests something unintended, namely, mental acts of abstraction; but the term is in use, and I'll use it. An abstract entity is one that is not located in space or time and is not causally active or passive. Take a humble arithmetical truth such as 7 + 5 = 12. The truth expressed (which is not to be confused with the sentences used to express it or the thoughts used to think it) can exist and be true whether any World 2 entities exist and whether any World 1 entities exist. I won't trot out all the arguments for this; I'll simply refer the reader to Frege, Popper, et al. Now suppose some benighted soul came along who got it into his head to build a "gradualist bridge" (to use a phrase of Dennett) from World 1 (the physical world) to World 3. He thinks that by a sufficiently deep and protracted investigation of the physical world we can come to explain abstracta as ultimately physical in nature. He thinks that if we only knew enough physics we would be able to understand that there is no independent realm of abstracta. One ought to be able to see that there is something utterly absurd about building a "gradualist bridge" from World 1 to World 3. Why, exactly? Well, physics presupposes mathematics; hence the truths of the latter cannot be reduced to truths of the former. For example, from pure mathematics we know that if d = vt, then v = d/t. That is a necessary truth, true in all possible worlds, including those in which there is no space, time, or moving particles. As such, it cannot be verified or refuted by any empirical test.
Kevin is in good company, however. An awful lot of modern philosophy (~ 1800 to the present) would lead one to the same conclusions. Too bad for modern philosophy.

Comments

Popular posts from this blog

The Hiatus will be blogged

This hiatus thing isn't going to plan. As I'm reading (books and blogs) I find things I think are interesting, or things I would like an opinion on, and bingo, my hiatus is in a shambles. So, *coughs*, until further notice, I'm blogging again. The main editorial difference that I can see coming from my few weeks away is that I do not expect to resume posting six out of seven days a week. There could be, at any time and without warning, a break of a week or two between posts. Really, I think that is the only way I can start to get some books behind me, and is also inevitable in the summer season when one wants to get out and enjoy it all. Here's a few things that got my attention this past week. Chris Taylor is blogging once again and has recruited an air force for the Red Ensign Brigade. Heh. Dennis Prager asks, Are you a liberal? Anglicans and Catholics are getting closer to reconciling -over the role of Mary in the Christian faith. Quote: A working group c...

Ghost in the machine

In writing up this post I have to mention that I am very impressed with the quality of discussion that one finds on blogs. This truly is a remarkable medium. Thanks go to all three of the bloggers mentioned here for providing such good reading and thinking for the rest of us to try and learn from. I have not had a chance to read all of the entries linked to here, but I do intend to. ***** George Will compares two views of man in his latest column . One is novelist Ian McEwan, who places the following words into the mouth of the leading character in his latest novel, Saturday : Endless and beautiful forms of life, such as you see in a common hedgerow, including exulted beings like ourselves, arose from physical laws, from war or nature, famine and death. This is the grandeur. And a bracing kind of consolation in the brief privilege of consciousness. This character is a neurosurgeon. The quote reminds me that there may be some truth to the observation that those in the biological and...