Thursday, May 24, 2007

Modal Copulation and Satisfaction. by Jessica Leech

Many philosophers, for various reasons, feel uncomfortable with the use of possible world semantics in an explanation of modal language (fragments of natural language including modal locutions such as ‘possibly’, ‘necessarily’, ‘must’, ‘could be’, etc.). A common alternative suggestion is that we analyse modal statements in terms of modal predicates and/or modal properties. For example, “Socrates is necessarily a man” is understood as something like predication of ‘being necessarily male’ of Socrates. An amendment, and rival, of this approach understands the modal term, not as modifying the predicate, i.e. from ‘male’ to ‘necessarily male’, but as modifying the copula, i.e. from ‘is’ to ‘is necessarily’.

This kind of approach adheres to the intuition that de re modality is somehow involved with the relation between an object and a property, rather than being involved in the inception of new predicates and new properties. This can be illustrated by the difference between asking, ‘Is Socrates necessarily wise, or is he just contingently so?’, and asking which of two properties Socrates has, (contingent) wisdom or necessary wisdom?

McGinn, in his book Logical Properties, presents such a copula modifier account of modality. He claims that a statement of the form “a is [modally] F” is true just when a [modally] satisfies “is F”. So, for example, “Socrates is necessarily wise” is true iff Socrates necessarily satisfies the predicate “is wise”. Modal satisfaction is in turn explained in terms of modal instantiation. So, Socrates necessarily satisfies “is wise” iff Socrates necessarily instantiates wisdom.

The challenge for modal copula accounts that employ “modal satisfaction” is to flesh out this new semantic notion. McGinn’s strategy is to appeal to modes of instantiation. He claims that there are two and only two modes of instantiation, necessary and contingent. Our statements might leave this as neutral, e.g. “Socrates is wise”, but at the worldly level, where we find Socrates and wisdom, if they bear the instantiation relation to each another, then they bear that relation in one or other mode.

The problem with this theory is that there is no way to accommodate mere possibility. Firstly, it is prima facie unclear how one could begin to understand possible instantiation as a mode of instantiation, where there need be no actual instantiation, but there is only mere possibility. More worrying, a contradiction can be generated:

(1) “Socrates is possibly foolish” is true.
(2) So Socrates contingently instantiates foolishness.
(3) So, Socrates instantiates foolishness.
(4) “Socrates is not foolish” is true.
(5) So Socrates does not instantiate foolishness.
Contradiction!

In order to give the copula modifier account of modality fair trial, we cannot follow McGinn’s lead. We must either find an alternative way to understand modal satisfaction, or find a better way to make sense of copula modification than in terms of modification of satisfaction.

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Thursday, May 03, 2007

I am immortal

Last nights talk was on immortality in the context of Plato and Aristotle. Considering that 40% of the worlds population testify to believing in life after death in one form or another it should still be considered a live issue. I for one became interested in philosophy through a morbid fascination with my own death and saw a possible way out in Plato’s republic. Here is what it is: good things perish, but goodness itself is eternal. “Eternal” can be seen not to signify a very long period of time, but timeless, unchanging, outside time. In the same way people can use the term “priceless” to mean very expensive. In particular contexts “priceless” can mean £150 000. But really priceless means not being measurable in money at all. Eternal then can be thought of as not being measured in time. Could our souls be eternal in this sense?
It seems that our souls participate in goodness in an essential way. Goodness is the light by which we understand things. This is not a contemporary thought. English speaking philosophers tend to think we understand things in terms of their truth conditions. But if we don’t know the value of something, then there is a very real sense in which we do not know that thing at all.
So my version of Plato’s version of Socrates version of the immortality of the soul is that when we understand things, we participate in the good, so in understanding we are eternal.
This is good enough for me, it certainly feels that way when one thinks a certain type of thought. “I think therefore I am”. This is always a valid argument, whoever thinks it. Either “I” is an indexical, or we are all immortal whenever we think this thought.
However, I suspect that the two billion people who believe in life after death want the afterlife to be a bit more personal than this.

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