« Is Philosophy the Most Practical Major? | Main | "Europe is the Faith and the Faith is Europe" »

Tuesday, October 18, 2011


Feed You can follow this conversation by subscribing to the comment feed for this post.


Sorry I don't get this "the Necessity of Identity" principle. Take this example:
"Obama is the president of the US"
Is this an identity? If so, is this a necessary identity?

Good comment, arash. The principle holds when proper names flank the identity sign. 'The president of the US,' however, is not a proper name but a definite description. When read attributively as opposed to referentially it allows for possible worlds in which Obama is not the present president of the US.

There may be a line of defense for Hennessey here. He wants to read the predication 'Socrates is seated' as the identity sentence, 'Socrates is identical to a seated being.' Now what exactly is the logical status of 'a seated being'? It is not a logically proper name. It is an indefinite description.

'Socrates is identical to a seated being' does not sound right. Because if:
1. 'X is seated' means 'X is identical to a seated being'
2. 'Socrates is seated' and 'Obama is seated' are both true
3. Identity is transitive
4. 'Socrates is identical to a seated being' and 'Obama is identical to a seated being' are both true (for 1 and 2)
5. 'Obama is identical to Socrates' is true (for 4 and 3)

Hennessey would probably say that 'a seated being' means 'some seated being or other' in which case the inference to (5) fails.

The comments to this entry are closed.

My Photo
Blog powered by Typepad
Member since 10/2008



May 2024

Sun Mon Tue Wed Thu Fri Sat
      1 2 3 4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31  
Blog powered by Typepad