display all the ideas for this combination of texts
7 ideas
11380 | Two things with the same primary being and essence are one thing [Aristotle] |
Full Idea: If any two items have a single substance [ousia, primary being] and a single what-it-is-to-be-that-thing [to ti en einai, essence], then they are themselves a single thing. | |
From: Aristotle (Metaphysics [c.324 BCE], 1038b14) | |
A reaction: [alternative translations by Vasilis Politis] This isn't quite the identity of indiscernibles, because it allows superficial identity along with deep difference (H2O and XYZ, for example, or jadeite and nephrite). |
4640 | If identity is based on 'true of X' instead of 'property of X' we get the Masked Man fallacy ('I know X but not Y') [Baggini /Fosl, by PG] |
Full Idea: The Masked Man fallacy is when Leibniz's Law is taken as 'X and Y are identical if what is true of X is true of Y' (rather than being about properties). Then 'I know X' but 'I don't know Y' (e.g. my friend wearing a mask) would make X and Y non-identical. | |
From: report of J Baggini / PS Fosl (The Philosopher's Toolkit [2003], §3.17) by PG - Db (ideas) | |
A reaction: As the book goes on to explain, Descartes is guilty of this when arguing that I necessarily know my mind but not my body, so they are different. Seems to me that Kripke falls into the same trap. |
17848 | Things such as two different quadrangles are alike but not wholly the same [Aristotle] |
Full Idea: Things are alike if they are not just the same simpliciter, exhibiting differences in their substrate substance but being formally the same. Examples are larger and smaller quadrangles and unequal straight lines, which are alike but not the same. | |
From: Aristotle (Metaphysics [c.324 BCE], 1054b06) |
4647 | 'I have the same car as you' is fine; 'I have the same fiancée as you' is not so good [Baggini /Fosl] |
Full Idea: If you found that I had the same car as you, I don't suppose you would care, but if you found I had the same fiancée as you, you might not be so happy. | |
From: J Baggini / PS Fosl (The Philosopher's Toolkit [2003], §4.17) | |
A reaction: A very nice illustration of the ambiguity of "same", and hence of identity. 'I had the same thought as you'. 'I have the same DNA as you'. |
17847 | You are one with yourself in form and matter [Aristotle] |
Full Idea: You are one with yourself both in form and in matter. | |
From: Aristotle (Metaphysics [c.324 BCE], 1054a35) |
16134 | We can't understand self-identity without a prior grasp of the object [Aristotle] |
Full Idea: To ask why a thing is identical with itself is not to ask a real question in the absence of a clear grasp of the fact ….or of the object. | |
From: Aristotle (Metaphysics [c.324 BCE], 1041a12) | |
A reaction: This seems a very nice response to Lewis's attempt to sweep difficulties of identity aside, when he rests identity on primitive self-identity. |
4639 | Leibniz's Law is about the properties of objects; the Identity of Indiscernibles is about perception of objects [Baggini /Fosl] |
Full Idea: Leibniz's Law ('if identical, must have same properties') defines identity according to the properties possessed by the object itself, but the Identity of Indiscernibles defines identity in terms of how things are conceived or grasped by the mind. | |
From: J Baggini / PS Fosl (The Philosopher's Toolkit [2003], §3.16) | |
A reaction: This is the heart of the problem of identity. We realists must fight for Leibniz's Law, and escort the Identity of Indiscernibles to the door. |