8 ideas
| 2945 | Most philosophers start with reality and then examine knowledge; Descartes put the study of knowledge first [Lehrer] |
| Full Idea: Some philosophers (e.g Plato) begin with an account of reality, and then appended an account of how we can know it, ..but Descartes turned the tables, insisting that we must first decide what we can know. | |
| From: Keith Lehrer (Theory of Knowledge (2nd edn) [2000], I p.2) |
| 2946 | You cannot demand an analysis of a concept without knowing the purpose of the analysis [Lehrer] |
| Full Idea: An analysis is always relative to some objective. It makes no sense to simply demand an analysis of goodness, knowledge, beauty or truth, without some indication of the purpose of the analysis. | |
| From: Keith Lehrer (Theory of Knowledge (2nd edn) [2000], I p.7) | |
| A reaction: Your dismantling of a car will go better if you know what a car is for, but you can still take it apart in ignorance. |
| 16597 | Quantity is the capacity to be divided [Digby] |
| Full Idea: Quantity …is divisibility, or a capacity to be divided into parts. | |
| From: Kenelm Digby (Two treatises [1644], I.2.8), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 04.1 | |
| A reaction: 'Quantity' is scholastic philosophy is a concept we no longer possess. Without quantity, a thing might potentially exist at a spaceless point. Quantity is what spreads things out. See Pasnau Ch. 4. |
| 9329 | Justification is coherence with a background system; if irrefutable, it is knowledge [Lehrer] |
| Full Idea: Justification is coherence with a background system which, when irrefutable, converts to knowledge. | |
| From: Keith Lehrer (Consciousness,Represn, and Knowledge [2006]) | |
| A reaction: A problem (as the theory stands here) would be whether you have to be aware that the coherence is irrefutable, which would seem to require a pretty powerful intellect. If one needn't be aware of the irrefutability, how does it help my justification? |
| 9330 | Generalization seems to be more fundamental to minds than spotting similarities [Lehrer] |
| Full Idea: There is a level of generalization we share with other animals in the responses to objects that suggest that generalization is a more fundamental operation of the mind than the observation of similarities. | |
| From: Keith Lehrer (Consciousness,Represn, and Knowledge [2006]) | |
| A reaction: He derives this from Reid (1785) - Lehrer's hero - who argued against Hume that we couldn't spot similarities if we hadn't already generalized to produce the 'respect' of the similarity. Interesting. I think Reid must be right. |
| 9328 | All conscious states can be immediately known when attention is directed to them [Lehrer] |
| Full Idea: I am inclined to think that all conscious states can be immediately known when attention is directed to them. | |
| From: Keith Lehrer (Consciousness,Represn, and Knowledge [2006]) | |
| A reaction: This strikes me as a very helpful suggestion, for eliminating lots of problem cases for introspective knowledge which have been triumphally paraded in recent times. It might, though, be tautological, if it is actually a definition of 'conscious states'. |
| 6005 | Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley] |
| Full Idea: Hermarchus said that animal killing is justified by considerations of human safety and nourishment and by animals' inability to form contractual relations of justice with us. | |
| From: report of Hermarchus (fragments/reports [c.270 BCE]) by David A. Sedley - Hermarchus | |
| A reaction: Could the last argument be used to justify torturing animals? Or could we eat a human who was too brain-damaged to form contracts? |
| 16731 | Colours arise from the rarity, density and mixture of matter [Digby] |
| Full Idea: The origin of all colours in bodies is plainly deduced out of the various degrees of rarity and density, variously mixed and compounded. | |
| From: Kenelm Digby (Two treatises [1644], I.29.4), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 22.5 | |
| A reaction: We are still struggling with this question, though I think the picture is gradually become clear, once you get the hang of the brain. Easy! See Idea 17396. |