Prof. Paul,

I read with interest your "In Defense of Essentialism." First, here are some typos I found; they're pretty straightforward for the most part:

[snip]

Secondly, I thought I would offer a brief response to your call for "a generally acceptable reductive account of how spatiotemporal composition is restricted" (365).

Take a little Kantian framework, in which we have a physical realm composed of who knows what (noumena), and a mental realm in which our consciousness actually plays out. Now suppose mereological composition and decomposition are two primitive mental functions. Under this system, all objects under mereological consideration are only ever mental objects. These are dirt cheap, addressing the grievance "that there exist so many objects with so many different modal profiles, even if we usually ignore most of them" (363). As to why we ignore most of them, I suggest a criterion of fruitfulness: the suitability of a composition to further composition. That is, yes, "there is an object that is the sum of [your] microwave and the top of Mt. Everest" (363), but you can't do anything with it. It doesn't lend itself to further composition. It is a mereological dead end. A philosopher may explore it, but common sense is preserved.

If mereological composition is driven by fruitfulness, then mereological level is not just another arbitrary context of evaluation, so deep essentialism survives on that count. The challenge then becomes accounting for translation across mental realms, since we each have our own. Not only that, but it also seems here that within a given mental realm, objects only actually exist at certain mereological levels, and perhaps only during cognition. (Does Car exist while you're cognizing Sprocket?) But once mental objects are granted reality at all--and for a Kantian cognizer, a mental object is as real as it gets--these complexities could probably be dealt with.

I think a system something like the above could also be fruitfully used, for example, in addressing the Problem of the Many. In any case, I'd be interested to hear whether you find anything worthwhile here.

Thanks for your work.

yours,

Chad Whitacre

chad@zetaweb.com