5 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. |
10558 | Abstract objects are actually constituted by the properties by which we conceive them [Zalta] |
Full Idea: Where for ordinary objects one can discover the properties they exemplify, abstract objects are actually constituted or determined by the properties by which we conceive them. I use the technical term 'x encodes F' for this idea. | |
From: Edward N. Zalta (Deriving Kripkean Claims with Abstract Objects [2006], 2 n2) | |
A reaction: One might say that whereas concrete objects can be dubbed (in the Kripke manner), abstract objects can only be referred to by descriptions. See 10557 for more technicalities about Zalta's idea. |
17555 | 'One' can mean undivided and not a multitude, or it can add measurement, giving number [Aquinas] |
Full Idea: There are two sorts of one. There is the one which is convertible with being, which adds nothing to being except being undivided; and this deprives of multitude. Then there is the principle of number, which to the notion of being adds measurement. | |
From: Thomas Aquinas (Quaestiones de Potentia Dei [1269], q3 a16 ad 3-um) | |
A reaction: [From a lecture handout] I'm not sure I understand this. We might say, I suppose, that insofar as water is water, it is all one, but you can't count it. Perhaps being 'unified' and being a 'unity' are different? |
10557 | Abstract objects are captured by second-order modal logic, plus 'encoding' formulas [Zalta] |
Full Idea: My object theory is formulated in a 'syntactically second-order' modal predicate calculus modified only so as to admit a second kind of atomic formula ('xF'), which asserts that object x 'encodes' property F. | |
From: Edward N. Zalta (Deriving Kripkean Claims with Abstract Objects [2006], p.2) | |
A reaction: This is summarising Zalta's 1983 theory of abstract objects. See Idea 10558 for Zalta's idea in plain English. |