Saturday, September 02, 2006

Albert of Saxony on Chimaera

I say that when the subject and predicate of an affirmative proposition do not stand for anything at all, such a proposition is always false; for example, if I say 'A chimaera is a chimaera,' 'A chimaera can be thought of,' or 'A chimaera can be understood.' This is evident, for since the proposition is affirmative, and not selffalsifying, and since it is required for the truth of such a proposition that its subject and predicate stand for the same, it follows that this proposition, which is affirmative and whose subject does not stand for anything, is false. For in this proposition the subject and predicate do not stand for the same thing, because they do not stand for anything; yet this is required for the truth of any affirmative proposition such as is not selffalsifying.

Fifth, I say that a negative proposition, whose subject stands for nothing, is true. From this it follows that this sentence is true, 'A chimaera is not a chimaera'; similarly this, 'A vacuum is not a vacuum,' or this, 'A chimaera is not intelligible.'

But against this it is argued that this proposition, 'A chimaera is a chimaera', is true, because the same thing is here predicated of itself. Now according to Boethius, in his commentary on the Categories, there is no truer predication than that in which something is predicated of itself. And that this occurs here is evident. In the second place, Aristotle in the 7th book of the Metaphysics concedes the truth of this proposition 'Not being is not being' (Non ens eat non ens), and yet this is an affirmative proposition whose subject stands for nothing.

To the first argument we respond that when it is said that Boethius says that nothing is truer than the predication of the same thing of itself, this is to be conceded if in that proposition the terms stand for something. But if the terms do not stand for anything, the proposition can be false; and this is so in the case of the sentence 'A chimaera is a chimaera.' To the second argument I say that in this proposition 'Not being is not being', the first negative may be construed as determining the term to which it is joined, in such manner that the copula remains affirmative; and in such a case the proposition is affirmative, and is false. But it is not in this sense that Aristotle concedes it to be true. In another sense it can be understood so that the first negative determines the proposition as a whole, such that the sense is 'It is not the case that a being is not a being' (non:ens est non ens)---i.e., meaning that it is not true that a being is a non-being. And in this sense the proposition is true, but it is negative and not affirmative. In a similar manner one can distinguish two senses of this proposition 'No thing is no thing' (nihil est nihil).


Blogger Ocham said...

You may be interested in this translation (From the Logic Museum) of II.14 from Ockham's Summa, which has some affinities with this passage.

8:55 AM  

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