display all the ideas for this combination of philosophers
2 ideas
| 8983 | If 'red' is vague, then membership of the set of red things is vague, so there is no set of red things [Sainsbury] |
| Full Idea: Sets have sharp boundaries, or are sharp objects; an object either definitely belongs to a set, or it does not. But 'red' is vague; there objects which are neither definitely red nor definitely not red. Hence there is no set of red things. | |
| From: Mark Sainsbury (Concepts without Boundaries [1990], §2) | |
| A reaction: Presumably that will entail that there IS a set of things which can be described as 'definitely red'. If we describe something as 'definitely having a hint of red about it', will that put it in a set? In fact will the applicability of 'definitely' do? |
| 13417 | If a mathematical structure is rejected from a physical theory, it retains its mathematical status [Parsons,C] |
| Full Idea: If experience shows that some aspect of the physical world fails to instantiate a certain mathematical structure, one will modify the theory by sustituting a different structure, while the original structure doesn't lose its status as part of mathematics. | |
| From: Charles Parsons (Review of Tait 'Provenance of Pure Reason' [2009], §2) | |
| A reaction: This seems to be a beautifully simple and powerful objection to the Quinean idea that mathematics somehow only gets its authority from physics. It looked like a daft view to begin with, of course. |