71 ideas
| 19336 | Wisdom involves the desire to achieve perfection [Leibniz] |
| 21955 | My dogmatic slumber was first interrupted by David Hume [Kant] |
| 16931 | Metaphysics is generating a priori knowledge by intuition and concepts, leading to the synthetic [Kant] |
| 18835 | Logic doesn't have a metaphysical basis, but nor can logic give rise to the metaphysics [Rumfitt] |
| 18819 | The idea that there are unrecognised truths is basic to our concept of truth [Rumfitt] |
| 18826 | 'True at a possibility' means necessarily true if what is said had obtained [Rumfitt] |
| 18803 | Semantics for propositions: 1) validity preserves truth 2) non-contradition 3) bivalence 4) truth tables [Rumfitt] |
| 18814 | 'Absolute necessity' would have to rest on S5 [Rumfitt] |
| 18798 | It is the second-order part of intuitionistic logic which actually negates some classical theorems [Rumfitt] |
| 18799 | Intuitionists can accept Double Negation Elimination for decidable propositions [Rumfitt] |
| 18830 | Most set theorists doubt bivalence for the Continuum Hypothesis, but still use classical logic [Rumfitt] |
| 18843 | The iterated conception of set requires continual increase in axiom strength [Rumfitt] |
| 18836 | A set may well not consist of its members; the empty set, for example, is a problem [Rumfitt] |
| 18837 | A set can be determinate, because of its concept, and still have vague membership [Rumfitt] |
| 18845 | If the totality of sets is not well-defined, there must be doubt about the Power Set Axiom [Rumfitt] |
| 18815 | Logic is higher-order laws which can expand the range of any sort of deduction [Rumfitt] |
| 18804 | The case for classical logic rests on its rules, much more than on the Principle of Bivalence [Rumfitt] |
| 18805 | Classical logic rules cannot be proved, but various lines of attack can be repelled [Rumfitt] |
| 18827 | If truth-tables specify the connectives, classical logic must rely on Bivalence [Rumfitt] |
| 18813 | Logical consequence is a relation that can extended into further statements [Rumfitt] |
| 18808 | Normal deduction presupposes the Cut Law [Rumfitt] |
| 18840 | When faced with vague statements, Bivalence is not a compelling principle [Rumfitt] |
| 18802 | In specifying a logical constant, use of that constant is quite unavoidable [Rumfitt] |
| 18800 | Introduction rules give deduction conditions, and Elimination says what can be deduced [Rumfitt] |
| 18809 | Logical truths are just the assumption-free by-products of logical rules [Rumfitt] |
| 18807 | Monotonicity means there is a guarantee, rather than mere inductive support [Rumfitt] |
| 16918 | Mathematics cannot proceed just by the analysis of concepts [Kant] |
| 16930 | Geometry is not analytic, because a line's being 'straight' is a quality [Kant] |
| 16919 | Geometry rests on our intuition of space [Kant] |
| 16920 | Numbers are formed by addition of units in time [Kant] |
| 18842 | Maybe an ordinal is a property of isomorphic well-ordered sets, and not itself a set [Rumfitt] |
| 16929 | 7+5 = 12 is not analytic, because no analysis of 7+5 will reveal the concept of 12 [Kant] |
| 18834 | Infinitesimals do not stand in a determinate order relation to zero [Rumfitt] |
| 18846 | Cantor and Dedekind aimed to give analysis a foundation in set theory (rather than geometry) [Rumfitt] |
| 16910 | Mathematics can only start from an a priori intuition which is not empirical but pure [Kant] |
| 16917 | All necessary mathematical judgements are based on intuitions of space and time [Kant] |
| 16928 | Mathematics cannot be empirical because it is necessary, and that has to be a priori [Kant] |
| 7696 | Leibniz first asked 'why is there something rather than nothing?' [Leibniz, by Jacquette] |
| 19341 | There must be a straining towards existence in the essence of all possible things [Leibniz] |
| 19428 | Because something does exist, there must be a drive in possible things towards existence [Leibniz] |
| 11833 | The substance, once the predicates are removed, remains unknown to us [Kant] |
| 18839 | An object that is not clearly red or orange can still be red-or-orange, which sweeps up problem cases [Rumfitt] |
| 18838 | The extension of a colour is decided by a concept's place in a network of contraries [Rumfitt] |
| 18816 | Metaphysical modalities respect the actual identities of things [Rumfitt] |
| 18825 | S5 is the logic of logical necessity [Rumfitt] |
| 5047 | The world is physically necessary, as its contrary would imply imperfection or moral absurdity [Leibniz] |
| 18824 | Since possibilities are properties of the world, calling 'red' the determination of a determinable seems right [Rumfitt] |
| 18828 | If two possibilities can't share a determiner, they are incompatible [Rumfitt] |
| 18821 | Possibilities are like possible worlds, but not fully determinate or complete [Rumfitt] |
| 21957 | 'Transcendental' concerns how we know, rather than what we know [Kant] |
| 18831 | Medieval logicians said understanding A also involved understanding not-A [Rumfitt] |
| 16923 | I admit there are bodies outside us [Kant] |
| 21441 | 'Transcendental' is not beyond experience, but a prerequisite of experience [Kant] |
| 16916 | A priori synthetic knowledge is only of appearances, not of things in themselves [Kant] |
| 16915 | A priori intuitions can only concern the objects of our senses [Kant] |
| 16914 | A priori intuition of objects is only possible by containing the form of my sensibility [Kant] |
| 21447 | I can make no sense of the red experience being similar to the quality in the object [Kant] |
| 16924 | I count the primary features of things (as well as the secondary ones) as mere appearances [Kant] |
| 16913 | I can't intuit a present thing in itself, because the properties can't enter my representations [Kant] |
| 16925 | Appearance gives truth, as long as it is only used within experience [Kant] |
| 16911 | Intuition is a representation that depends on the presence of the object [Kant] |
| 18820 | In English 'evidence' is a mass term, qualified by 'little' and 'more' [Rumfitt] |
| 16912 | Some concepts can be made a priori, which are general thoughts of objects, like quantity or cause [Kant] |
| 18817 | We understand conditionals, but disagree over their truth-conditions [Rumfitt] |
| 16926 | Analytic judgements say clearly what was in the concept of the subject [Kant] |
| 16927 | Analytic judgement rests on contradiction, since the predicate cannot be denied of the subject [Kant] |
| 18829 | The truth grounds for 'not A' are the possibilities incompatible with truth grounds for A [Rumfitt] |
| 19343 | We follow the practical rule which always seeks maximum effect for minimum cost [Leibniz] |
| 19429 | The principle of determination in things obtains the greatest effect with the least effort [Leibniz] |
| 16922 | Space must have three dimensions, because only three lines can meet at right angles [Kant] |
| 16921 | If all empirical sensation of bodies is removed, space and time are still left [Kant] |