15 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] |
3785 | You can't separate acts from the people performing them [Glover] |
3786 | Aggression in defence may be beneficial but morally corrupting [Glover] |
7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
3784 | Duty prohibits some acts, whatever their consequences [Glover] |
3782 | Satisfaction of desires is not at all the same as achieving happiness [Glover, by PG] |
3787 | Rule-utilitarianism is either act-utilitarianism, or not really utilitarian [Glover] |
3783 | How can utilitarianism decide the ideal population size? [Glover] |