61 ideas
21422 | Moral self-knowledge is the beginning of all human wisdom [Kant] |
21408 | For any subject, its system of non-experiential concepts needs a metaphysics [Kant] |
21416 | Philosophers should not offer multiple proofs - suggesting the weakness of each of them [Kant] |
9724 | Until the 1960s the only semantics was truth-tables [Enderton] |
9703 | 'dom R' indicates the 'domain' of objects having a relation [Enderton] |
9705 | 'fld R' indicates the 'field' of all objects in the relation [Enderton] |
9704 | 'ran R' indicates the 'range' of objects being related to [Enderton] |
9710 | We write F:A→B to indicate that A maps into B (the output of F on A is in B) [Enderton] |
9707 | 'F(x)' is the unique value which F assumes for a value of x [Enderton] |
9712 | A relation is 'symmetric' on a set if every ordered pair has the relation in both directions [Enderton] |
9713 | A relation is 'transitive' if it can be carried over from two ordered pairs to a third [Enderton] |
9699 | The 'powerset' of a set is all the subsets of a given set [Enderton] |
9700 | Two sets are 'disjoint' iff their intersection is empty [Enderton] |
9702 | A 'domain' of a relation is the set of members of ordered pairs in the relation [Enderton] |
9701 | A 'relation' is a set of ordered pairs [Enderton] |
9706 | A 'function' is a relation in which each object is related to just one other object [Enderton] |
9708 | A function 'maps A into B' if the relating things are set A, and the things related to are all in B [Enderton] |
9709 | A function 'maps A onto B' if the relating things are set A, and the things related to are set B [Enderton] |
9711 | A relation is 'reflexive' on a set if every member bears the relation to itself [Enderton] |
9714 | A relation satisfies 'trichotomy' if all pairs are either relations, or contain identical objects [Enderton] |
9717 | A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second [Enderton] |
9715 | An 'equivalence relation' is a reflexive, symmetric and transitive binary relation [Enderton] |
9716 | We 'partition' a set into distinct subsets, according to each relation on its objects [Enderton] |
9722 | Inference not from content, but from the fact that it was said, is 'conversational implicature' [Enderton] |
9718 | Validity is either semantic (what preserves truth), or proof-theoretic (following procedures) [Enderton] |
9721 | A logical truth or tautology is a logical consequence of the empty set [Enderton] |
9994 | A truth assignment to the components of a wff 'satisfy' it if the wff is then True [Enderton] |
9719 | A proof theory is 'sound' if its valid inferences entail semantic validity [Enderton] |
9720 | A proof theory is 'complete' if semantically valid inferences entail proof-theoretic validity [Enderton] |
9995 | Proof in finite subsets is sufficient for proof in an infinite set [Enderton] |
9996 | Expressions are 'decidable' if inclusion in them (or not) can be proved [Enderton] |
9997 | For a reasonable language, the set of valid wff's can always be enumerated [Enderton] |
21410 | That a concept is not self-contradictory does not make what it represents possible [Kant] |
9723 | Sentences with 'if' are only conditionals if they can read as A-implies-B [Enderton] |
21421 | Within nature man is unimportant, but as moral person he is above any price [Kant] |
21415 | Duty is impossible without prior moral feeling, conscience, love and self-respect [Kant] |
21409 | Moral principles do not involve feelings [Kant] |
21431 | The love of man is required in order to present the world as a beautiful and perfect moral whole [Kant] |
21437 | All morality directs the will to love of others' ends, and respect for others' rights [Kant] |
21429 | The duty of love is to makes the ends of others one's own [Kant] |
21411 | A duty of virtue is a duty which is also an end [Kant] |
21413 | Virtue is strong maxims for duty [Kant] |
21414 | The supreme principle of virtue is to find universal laws for ends [Kant] |
21436 | We are obliged to show the social virtues, but at least they make a virtuous disposition fashionable [Kant] |
21419 | If virtue becomes a habit, that is a loss of the freedom needed for adopting maxims [Kant] |
21417 | How do we distinguish a mean? The extremes can involve quite different maxims [Kant] |
21420 | If virtue is the mean between vices, then virtue is just the vanishing of vice [Kant] |
21418 | There is one principle of virtues; the virtues are distinguished by their objects [Kant] |
21425 | We can love without respect, and show respect without love [Kant] |
21427 | Respect is limiting our self-esteem by attending to the human dignity of other persons [Kant] |
21430 | Disrespect is using a person as a mere means to my own ends [Kant] |
21428 | Respect is purely negative (of not exalting oneself over others), and is thus a duty of Right [Kant] |
21426 | Love urges us to get closer to people, but respect to keep our distance [Kant] |
21434 | We must respect the humanity even in a vicious criminal [Kant] |
21412 | Humans are distinguished from animals by their capacity to set themselves any sort of end [Kant] |
21435 | Man is both social, and unsociable [Kant] |
21433 | Violation of rights deserves punishment, which is vengeance, rather than restitution [Kant] |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
21423 | Men can only have duties to those who qualify as persons [Kant] |
21424 | Cruelty to animals is bad because it dulls our empathy for pain in humans [Kant] |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |