14 ideas
12170 | Amusement rests on superiority, or relief, or incongruity [Scruton] |
12173 | The central object of amusement is the human [Scruton] |
12169 | Since only men laugh, it seems to be an attribute of reason [Scruton] |
12172 | Objects of amusement do not have to be real [Scruton] |
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] |
12174 | Only rational beings are attentive without motive or concern [Scruton] |
468 | Musical performance can reveal a range of virtues [Damon of Ath.] |