8 ideas
| 8203 | All the arithmetical entities can be reduced to classes of integers, and hence to sets [Quine] |
| Full Idea: The arithmetic of ratios and irrational and imaginary numbers can all be reduced by definition to the theory of classes of positive integers, and this can in turn be reduced to pure set theory. | |
| From: Willard Quine (Vagaries of Definition [1972], p.53) | |
| A reaction: This summarises Quine's ontology of mathematics, which tries to eliminate virtually everything, but has to affirm the existence of sets. Can you count sets and their members, if the sets are used to define the numbers? |
| 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) |
| 22109 | The fullest knowledge places a conclusion within an accurate theory [Aquinas, by Kretzmann/Stump] |
| Full Idea: Having 'scientia' is the fullest possible human cognition, by which one situates the fact expressed by a conclusion in an explanatory theory that accurately maps metaphysical or physical reality. | |
| From: report of Thomas Aquinas (Sententia on 'Posterior Analytics' [1269], 1.2.9, 1.5.7) by Kretzmann/Stump - Aquinas, Thomas 11 | |
| A reaction: That is a perfect statement of my concept of knowledge. Explanatory theories must specify the essential natures of the entities involved. We don't aim for 'knowledge', we aim for the 'fullest possible cognition'. This account extend's Aristotle's. |
| 8202 | Meaning is essence divorced from things and wedded to words [Quine] |
| Full Idea: Meaning is essence divorced from the thing and wedded to the word. | |
| From: Willard Quine (Vagaries of Definition [1972], p.51) | |
| A reaction: Quine's strategy is that a demolition of essences will be a definition of meaning. Personally I would like to defend essences, though I admit to finding meaning tricky. That is because essences are external, but meanings are in minds. |
| 8201 | The distinction between meaning and further information is as vague as the essence/accident distinction [Quine] |
| Full Idea: The distinction between what belongs to the meaning of a word and what counts as further information is scarcely clearer than the distinction between the essence of a thing and its accidents. | |
| From: Willard Quine (Vagaries of Definition [1972], p.51) | |
| A reaction: In lots of cases the distinction between essence and accident strikes me as totally clear. Tricky borderline cases don't destroy a distinction. That bachelors are married is clearly not 'further information'. |