8 ideas
| 3653 | My Meditations are the complete foundation of my physics [Descartes] |
| Full Idea: My six Meditations contain all the foundations of my physics, …and their principles destroy those of Aristotle. | |
| From: René Descartes (Letters to Mersenne [1640], 1641.01.28) |
| 4736 | Truth is such a transcendentally clear notion that it cannot be further defined [Descartes] |
| Full Idea: Truth is such a transcendentally clear notion that it cannot be further defined. | |
| From: René Descartes (Letters to Mersenne [1640], 1642), quoted by Pascal Engel - Truth Intro | |
| A reaction: This is the view endorsed by Davidson. It is tempting to take basic concepts as axiomatic, but philosophers can't make that move every time they are in trouble. I have to say, though, that truth is a good candidate. |
| 10580 | Mathematics is both necessary and a priori because it really consists of logical truths [Yablo] |
| Full Idea: Mathematics seems necessary because the real contents of mathematical statements are logical truths, which are necessary, and it seems a priori because logical truths really are a priori. | |
| From: Stephen Yablo (Abstract Objects: a Case Study [2002], 10) | |
| A reaction: Yablo says his logicism has a Kantian strain, because numbers and sets 'inscribed on our spectacles', but he takes a different view (in the present Idea) from Kant about where the necessity resides. Personally I am tempted by an a posteriori necessity. |
| 10579 | Putting numbers in quantifiable position (rather than many quantifiers) makes expression easier [Yablo] |
| Full Idea: Saying 'the number of Fs is 5', instead of using five quantifiers, puts the numeral in quantifiable position, which brings expressive advantages. 'There are more sheep in the field than cows' is an infinite disjunction, expressible in finite compass. | |
| From: Stephen Yablo (Abstract Objects: a Case Study [2002], 08) | |
| A reaction: See Hofweber with similar thoughts. This idea I take to be a key one in explaining many metaphysical confusions. The human mind just has a strong tendency to objectify properties, relations, qualities, categories etc. - for expression and for reasoning. |
| 10577 | Concrete objects have few essential properties, but properties of abstractions are mostly essential [Yablo] |
| Full Idea: Objects like me have a few essential properties, and numerous accidental ones. Abstract objects are a different story. The intrinsic properties of the empty set are mostly essential. The relations of numbers are also mostly essential. | |
| From: Stephen Yablo (Abstract Objects: a Case Study [2002], 01) |
| 10578 | We are thought to know concreta a posteriori, and many abstracta a priori [Yablo] |
| Full Idea: Our knowledge of concreta is a posteriori, but our knowledge of numbers, at least, has often been considered a priori. | |
| From: Stephen Yablo (Abstract Objects: a Case Study [2002], 02) |
| 9220 | Lewis must specify that all possibilities are in his worlds, making the whole thing circular [Shalkowski, by Sider] |
| Full Idea: If purple cows are simply absent from Lewis's multiverse, then certain correct propositions turn out to be impossible. Lewis must require a world for every possibility. But then it is circular, as the multiverse needs modal notions to characterize it. | |
| From: report of Scott Shalkowski (Ontological Ground of Alethic Modality [1994], 3.9) by Theodore Sider - Reductive Theories of Modality 3.9 | |
| A reaction: [Inversely, a world containing a round square would make that possible] This sounds very nice, though Sider rejects it (p.197). I've never seen how you could define possibility using the concept of 'possible' worlds. |
| 3652 | I can't prove the soul is indestructible, only that it is separate from the mortal body [Descartes] |
| Full Idea: I don't know how to demonstrate that God cannot annihilate the soul, but only that it is entirely distinct from the body, and consequently that it is not naturally subject to die with it, which is all that is required to establish religion. | |
| From: René Descartes (Letters to Mersenne [1640], 1640.02.24) |