55 ideas
| 7786 | Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [Girle] |
| 7798 | There are three axiom schemas for propositional logic [Girle] |
| 7799 | Proposition logic has definitions for its three operators: or, and, and identical [Girle] |
| 7797 | Axiom systems of logic contain axioms, inference rules, and definitions of proof and theorems [Girle] |
| 7794 | There are seven modalities in S4, each with its negation [Girle] |
| 7793 | ◊p → □◊p is the hallmark of S5 [Girle] |
| 7795 | S5 has just six modalities, and all strings can be reduced to those [Girle] |
| 7787 | Possible worlds logics use true-in-a-world rather than true [Girle] |
| 7788 | Modal logic has four basic modal negation equivalences [Girle] |
| 7796 | Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle] |
| 7789 | Necessary implication is called 'strict implication'; if successful, it is called 'entailment' [Girle] |
| 7790 | If an argument is invalid, a truth tree will indicate a counter-example [Girle] |
| 5953 | For the Cyrenaics experience was not enough to give certainty about reality [Aristippus young, by Plutarch] |
| 15682 | Even fairly simple animals make judgements based on categories [Gelman] |
| 15691 | Children accept real stable categories, with nonobvious potential that gives causal explanations [Gelman] |
| 15700 | In India, upper-castes essentialize caste more than lower-castes do [Gelman] |
| 15685 | Essentialism is either natural to us, or an accident of our culture, or a necessary result of language [Gelman] |
| 15684 | Children's concepts include nonobvious features, like internal parts, functions and causes [Gelman] |
| 15681 | Essentialism: real or representational? sortal, causal or ideal? real particulars, or placeholders? [Gelman] |
| 15678 | Essentialism says categories have a true hidden nature which gives an object its identity [Gelman] |
| 15683 | Sortals are needed for determining essence - the thing must be categorised first [Gelman] |
| 15697 | Kind (unlike individual) essentialism assumes preexisting natural categories [Gelman] |
| 15687 | Kinship is essence that comes in degrees, and age groups are essences that change over time [Gelman] |
| 15679 | Essentialism comes from the cognitive need to categorise [Gelman] |
| 15698 | We found no evidence that mothers teach essentialism to their children [Gelman] |
| 15709 | Essentialism is useful for predictions, but it is not the actual structure of reality [Gelman] |
| 15696 | Peope favor historical paths over outward properties when determining what something is [Gelman] |
| 7800 | Analytic truths are divided into logically and conceptually necessary [Girle] |
| 7801 | Possibilities can be logical, theoretical, physical, economic or human [Girle] |
| 7792 | A world has 'access' to a world it generates, which is important in possible worlds semantics [Girle] |
| 15707 | There is intentional, mechanical, teleological, essentialist, vitalist and deontological understanding [Gelman] |
| 15703 | Memories often conform to a theory, rather than being neutral [Gelman] |
| 15708 | Inductive success is rewarded with more induction [Gelman] |
| 15694 | Children overestimate the power of a single example [Gelman] |
| 15695 | Children make errors in induction by focusing too much on categories [Gelman] |
| 15692 | People tend to be satisfied with shallow explanations [Gelman] |
| 15680 | Folk essentialism rests on belief in natural kinds, in hidden properties, and on words indicating structures [Gelman] |
| 15686 | Labels may indicate categories which embody an essence [Gelman] |
| 15690 | Causal properties are seen as more central to category concepts [Gelman] |
| 15688 | Categories are characterized by distance from a prototype [Gelman] |
| 15689 | Theory-based concepts use rich models to show which similarities really matter [Gelman] |
| 15699 | Prelinguistic infants acquire and use many categories [Gelman] |
| 3023 | Even the foolish may have some virtues [Aristippus young, by Diog. Laertius] |
| 3026 | Actions are influenced by circumstances, so Cyrenaics say felons should be reformed, not hated [Aristippus young, by Diog. Laertius] |
| 3024 | Cyrenaics teach that honour, justice and shame are all based on custom and fashion [Aristippus young, by Diog. Laertius] |
| 3025 | For a Cyrenaic no one is of equal importance to himself [Aristippus young, by Diog. Laertius] |
| 3019 | No one pleasure is different from or more pleasant than another [Aristippus young, by Diog. Laertius] |
| 3021 | The Cyrenaics asserted that corporeal pleasures were superior to mental ones [Aristippus young, by Diog. Laertius] |
| 3027 | Cyrenaics say wise men are self-sufficient, needing no friends [Aristippus young, by Diog. Laertius] |
| 15693 | One sample of gold is enough, but one tree doesn't give the height of trees [Gelman] |
| 15701 | Nouns seem to invoke stable kinds more than predicates do [Gelman] |
| 15705 | Essentialism encourages us to think about the world scientifically [Gelman] |
| 15702 | Essentialism doesn't mean we know the essences [Gelman] |
| 15704 | Essentialism starts from richly structured categories, leading to a search for underlying properties [Gelman] |
| 15706 | A major objection to real essences is the essentialising of social categories like race, caste and occupation [Gelman] |