20 ideas
| 15118 | A successful Aristotelian 'definition' is what sciences produces after an investigation [Koslicki] |
| Full Idea: My current use of the Aristotelian term 'definition' is intended to correspond to what is typically accessible to a scientist only at the end of a successful investigation into the nature of a particular phenomenon. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.3.1) | |
| A reaction: It is crucial to understand that Aristotle's definitions could be several hundred pages long. It has nothing to do with dictionary definitions. He proposes 'nominal' and 'real' definitions. |
| 15116 | Essences cause necessary features, and definitions describe those necessary features [Koslicki] |
| Full Idea: Since essences cause the other necessary features of a thing, so definitions, as the linguistic correlates of essences, explain, together with other axioms, the propositions describing those necessary features. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.3.1) | |
| A reaction: This is nice and clear. Definitions are NOT essences - they are the linguistic correlates of essences, and mirror those essences. The necessary features are not the only things needing explanation. That picture is too passive. |
| 12461 | We believe all mathematical problems are solvable [Hilbert] |
| Full Idea: The thesis that every mathematical problem is solvable - we are all convinced that it really is so. | |
| From: David Hilbert (On the Infinite [1925], p.200) | |
| A reaction: This will include, for example, Goldbach's Conjecture (every even is the sum of two primes), which is utterly simple but with no proof anywhere in sight. |
| 12456 | I aim to establish certainty for mathematical methods [Hilbert] |
| Full Idea: The goal of my theory is to establish once and for all the certitude of mathematical methods. | |
| From: David Hilbert (On the Infinite [1925], p.184) | |
| A reaction: This is the clearest statement of the famous Hilbert Programme, which is said to have been brought to an abrupt end by Gödel's Incompleteness Theorems. |
| 9633 | No one shall drive us out of the paradise the Cantor has created for us [Hilbert] |
| Full Idea: No one shall drive us out of the paradise the Cantor has created for us. | |
| From: David Hilbert (On the Infinite [1925], p.191), quoted by James Robert Brown - Philosophy of Mathematics | |
| A reaction: This is Hilbert's famous refusal to accept any account of mathematics, such as Kant's, which excludes actual infinities. Cantor had laid out a whole glorious hierarchy of different infinities. |
| 12460 | We extend finite statements with ideal ones, in order to preserve our logic [Hilbert] |
| Full Idea: To preserve the simple formal rules of ordinary Aristotelian logic, we must supplement the finitary statements with ideal statements. | |
| From: David Hilbert (On the Infinite [1925], p.195) | |
| A reaction: I find very appealing the picture of mathematics as rooted in the physical world, and then gradually extended by a series of 'idealisations', which should perhaps be thought of as fictions. |
| 12462 | Only the finite can bring certainty to the infinite [Hilbert] |
| Full Idea: Operating with the infinite can be made certain only by the finitary. | |
| From: David Hilbert (On the Infinite [1925], p.201) | |
| A reaction: See 'Compactness' for one aspect of this claim. I think Hilbert was fighting a rearguard action, and his idea now has few followers. |
| 12455 | The idea of an infinite totality is an illusion [Hilbert] |
| Full Idea: Just as in the limit processes of the infinitesimal calculus, the infinitely large and small proved to be a mere figure of speech, so too we must realise that the infinite in the sense of an infinite totality, used in deductive methods, is an illusion. | |
| From: David Hilbert (On the Infinite [1925], p.184) | |
| A reaction: This is a very authoritative rearguard action. I no longer think the dispute matters much, it being just a dispute over a proposed new meaning for the word 'number'. |
| 12457 | There is no continuum in reality to realise the infinitely small [Hilbert] |
| Full Idea: A homogeneous continuum which admits of the sort of divisibility needed to realise the infinitely small is nowhere to be found in reality. | |
| From: David Hilbert (On the Infinite [1925], p.186) | |
| A reaction: He makes this remark as a response to Planck's new quantum theory (the year before the big works of Heisenberg and Schrödinger). Personally I don't see why infinities should depend on the physical world, since they are imaginary. |
| 12459 | The subject matter of mathematics is immediate and clear concrete symbols [Hilbert] |
| Full Idea: The subject matter of mathematics is the concrete symbols themselves whose structure is immediately clear and recognisable. | |
| From: David Hilbert (On the Infinite [1925], p.192) | |
| A reaction: I don't think many people will agree with Hilbert here. Does he mean token-symbols or type-symbols? You can do maths in your head, or with different symbols. If type-symbols, you have to explain what a type is. |
| 18112 | Mathematics divides in two: meaningful finitary statements, and empty idealised statements [Hilbert] |
| Full Idea: We can conceive mathematics to be a stock of two kinds of formulas: first, those to which the meaningful communications of finitary statements correspond; and secondly, other formulas which signify nothing and which are ideal structures of our theory. | |
| From: David Hilbert (On the Infinite [1925], p.196), quoted by David Bostock - Philosophy of Mathematics 6.1 |
| 15110 | An essence and what merely follow from it are distinct [Koslicki] |
| Full Idea: We can distinguish (as Aristotle and Fine do) between what belongs to the essence of an object, and what merely follows from the essence of an object. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.1) | |
| A reaction: This can help to clarify the confusions that result from treating necessary properties as if they were essential. |
| 15113 | Individuals are perceived, but demonstration and definition require universals [Koslicki] |
| Full Idea: Individual instances of a kind of phenomenon, in Aristotle's view, can only be perceived through sense-perception; but they are not the proper subject-matter of scientific demonstration and definition. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.3.1) | |
| A reaction: A footnote (11) explains that this is because they involve syllogisms, which require universals. I take Aristotle, and anyone sensible, to rest on individual essences, but inevitably turn to generic essences when language becomes involved. |
| 15112 | If an object exists, then its essential properties are necessary [Koslicki] |
| Full Idea: If an object has a certain property essentially, then it follows that the object has the property necessarily (if it exists). | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.2) | |
| A reaction: She is citing Fine, who says that the converse (necessity implying essence) is false. I agree with that. I also willing to challenge the first bit. I suspect an object can retain identity and lose essence. Coma patient; broken clock; aged athlete. |
| 9636 | My theory aims at the certitude of mathematical methods [Hilbert] |
| Full Idea: The goal of my theory is to establish once and for all the certitude of mathematical methods. | |
| From: David Hilbert (On the Infinite [1925], p.184), quoted by James Robert Brown - Philosophy of Mathematics Ch.5 | |
| A reaction: This dream is famous for being shattered by Gödel's Incompleteness Theorem a mere six years later. Neverless there seem to be more limited certainties which are accepted in mathematics. The certainty of the whole of arithmetic is beyond us. |
| 15111 | In demonstration, the explanatory order must mirror the causal order of the phenomena [Koslicki] |
| Full Idea: Demonstration encompasses more than deductive entailment, in that the explanatory order of priority represented in a successful demonstration must mirror precisely the causal order of priority present in the phenomena in question. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.1) | |
| A reaction: She is referring to Aristotle's 'Posterior Analytics'. Put so clearly this sounds like an incredibly useful concept in discussing how we present good modern scientific explanations. Reinstating Aristotle is a major priority for philosophy! |
| 15115 | In a demonstration the middle term explains, by being part of the definition [Koslicki] |
| Full Idea: In a proper demonstrative argument, the middle term must be explanatory of the conclusion, in a very specific sense: the middle term must state what properly belongs to the definition of the kind of phenomenon in question. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.3.1) | |
| A reaction: So 'All men are mortal, S is a man, so S is mortal'. The middle term is 'man', which gives a generic explanation for why S is mortal. Explanation as categorisation? I don't think this is the whole story of Aristotelian explanation. |
| 15117 | Greek uses the same word for 'cause' and 'explanation' [Koslicki] |
| Full Idea: The Greek does not disambiguate between 'cause' and 'explanation', since the same terms ('aitia' and 'aition') can be translated in both ways. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.3.1 n15) | |
| A reaction: This is essential information if we are to understand Aristotle's Four Causes, which are quite baffling if we take 'causes' in the modern way. The are the Four Modes of Explanation. |
| 15114 | Discovering the Aristotelian essence of thunder will tell us why thunder occurs [Koslicki] |
| Full Idea: Both the question 'what is thunder?', and the question 'why does thunder occur?', for Aristotle, are answered simultaneously, once it has been discovered what the essence of thunder it, i.e. what it is to be thunder. | |
| From: Kathrin Koslicki (Essence, Necessity and Explanation [2012], 13.3.1 n10) | |
| A reaction: I take this idea to be pretty much the whole story about essences. |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
| Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom. | |
| From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88) | |
| A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate'). |