35 ideas
| 8093 | Seek wisdom rather than truth; it is easier [Joubert] |
| 8095 | We must think with our entire body and soul [Joubert] |
| 8107 | The love of certainty holds us back in metaphysics [Joubert] |
| 8099 | The truths of reason instruct, but they do not illuminate [Joubert] |
| 8098 | Truth consists of having the same idea about something that God has [Joubert] |
| 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] |
| 10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
| 10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all 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] |
| 8101 | To know is to see inside oneself [Joubert] |
| 8094 | The imagination has made more discoveries than the eye [Joubert] |
| 8103 | A thought is as real as a cannon ball [Joubert] |
| 8100 | Where does the bird's idea of a nest come from? [Joubert] |
| 8096 | He gives his body up to pleasure, but not his soul [Joubert] |
| 8104 | What will you think of pleasures when you no longer enjoy them? [Joubert] |
| 8097 | Virtue is hard if we are scorned; we need support [Joubert] |
| 8106 | In raising a child we must think of his old age [Joubert] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
| 8105 | We can't exactly conceive virtue without the idea of God [Joubert] |
| 8102 | We cannot speak against Christianity without anger, or speak for it without love [Joubert] |