36 ideas
| 21959 | Metaphysics is the most general attempt to make sense of things [Moore,AW] |
| 19335 | Reasonings have a natural ordering in God's understanding, but only a temporal order in ours [Leibniz] |
| 10888 | Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo] |
| 10889 | The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo] |
| 10890 | A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo] |
| 10886 | Determinacy: an object is either in a set, or it isn't [Zalabardo] |
| 10887 | Specification: Determinate totals of objects always make a set [Zalabardo] |
| 10897 | A first-order 'sentence' is a formula with no free variables [Zalabardo] |
| 10893 | Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo] |
| 10899 | Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo] |
| 10896 | Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo] |
| 10898 | The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo] |
| 10902 | We can do semantics by looking at given propositions, or by building new ones [Zalabardo] |
| 10892 | We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo] |
| 10895 | 'Logically true' (|= φ) is true for every truth-assignment [Zalabardo] |
| 10900 | Logically true sentences are true in all structures [Zalabardo] |
| 10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo] |
| 10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
| 10903 | A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo] |
| 10891 | If a set is defined by induction, then proof by induction can be applied to it [Zalabardo] |
| 21958 | Appearances are nothing beyond representations, which is transcendental ideality [Moore,AW] |
| 19367 | Saying we must will whatever we decide to will leads to an infinite regress [Leibniz] |
| 19351 | Perfections of soul subordinate the body, but imperfections of soul submit to the body [Leibniz] |
| 19331 | Will is an inclination to pursue something good [Leibniz] |
| 19346 | Most people facing death would happily re-live a similar life, with just a bit of variety [Leibniz] |
| 19340 | Metaphysical evil is imperfection; physical evil is suffering; moral evil is sin [Leibniz] |
| 19366 | You can't assess moral actions without referring to the qualities of character that produce them [Leibniz] |
| 19326 | God must be intelligible, to select the actual world from the possibilities [Leibniz] |
| 19327 | The intelligent cause must be unique and all-perfect, to handle all the interconnected possibilities [Leibniz] |
| 19344 | God prefers men to lions, but might not exterminate lions to save one man [Leibniz] |
| 19330 | If justice is arbitrary, or fixed but not observed, or not human justice, this undermines God [Leibniz] |
| 19325 | God is the first reason of things; our experiences are contingent, and contain no necessity [Leibniz] |
| 19329 | The laws of physics are wonderful evidence of an intelligent and free being [Leibniz] |
| 19437 | Prayers are useful, because God foresaw them in his great plan [Leibniz] |
| 19337 | How can an all-good, wise and powerful being allow evil, sin and apparent injustice? [Leibniz] |
| 19345 | Being confident of God's goodness, we disregard the apparent local evils in the visible world [Leibniz] |