17 ideas
| 13201 | ∈ says the whole set is in the other; ⊆ says the members of the subset are in the other [Enderton] |
| 13204 | The 'ordered pair' <x,y> is defined to be {{x}, {x,y}} [Enderton] |
| 13206 | A 'linear or total ordering' must be transitive and satisfy trichotomy [Enderton] |
| 13200 | Note that {Φ} =/= Φ, because Φ ∈ {Φ} but Φ ∉ Φ [Enderton] |
| 13199 | The empty set may look pointless, but many sets can be constructed from it [Enderton] |
| 13203 | The singleton is defined using the pairing axiom (as {x,x}) [Enderton] |
| 13202 | Fraenkel added Replacement, to give a theory of ordinal numbers [Enderton] |
| 13205 | We can only define functions if Choice tells us which items are involved [Enderton] |
| 19400 | Possibles demand existence, so as many of them as possible must actually exist [Leibniz] |
| 19401 | God's sufficient reason for choosing reality is in the fitness or perfection of possibilities [Leibniz] |
| 19402 | The actual universe is the richest composite of what is possible [Leibniz] |
| 8353 | Freedom involves acting according to an idea [Anscombe] |
| 8352 | To believe in determinism, one must believe in a system which determines events [Anscombe] |
| 8351 | With diseases we easily trace a cause from an effect, but we cannot predict effects [Anscombe] |
| 4777 | The word 'cause' is an abstraction from a group of causal terms in a language (scrape, push..) [Anscombe] |
| 10363 | Causation is relative to how we describe the primary relata [Anscombe, by Schaffer,J] |
| 8350 | Since Mill causation has usually been explained by necessary and sufficient conditions [Anscombe] |