44 ideas
10859 | A set is 'well-ordered' if every subset has a first element [Clegg] |
10857 | Set theory made a closer study of infinity possible [Clegg] |
10864 | Any set can always generate a larger set - its powerset, of subsets [Clegg] |
10872 | Extensionality: Two sets are equal if and only if they have the same elements [Clegg] |
10875 | Pairing: For any two sets there exists a set to which they both belong [Clegg] |
10876 | Unions: There is a set of all the elements which belong to at least one set in a collection [Clegg] |
10878 | Infinity: There exists a set of the empty set and the successor of each element [Clegg] |
10877 | Powers: All the subsets of a given set form their own new powerset [Clegg] |
10879 | Choice: For every set a mechanism will choose one member of any non-empty subset [Clegg] |
10871 | Axiom of Existence: there exists at least one set [Clegg] |
10874 | Specification: a condition applied to a set will always produce a new set [Clegg] |
10880 | Mathematics can be 'pure' (unapplied), 'real' (physically grounded); or 'applied' (just applicable) [Clegg] |
10861 | Beyond infinity cardinals and ordinals can come apart [Clegg] |
10860 | An ordinal number is defined by the set that comes before it [Clegg] |
10854 | Transcendental numbers can't be fitted to finite equations [Clegg] |
10858 | By adding an axis of imaginary numbers, we get the useful 'number plane' instead of number line [Clegg] |
10853 | Either lack of zero made early mathematics geometrical, or the geometrical approach made zero meaningless [Clegg] |
10866 | Cantor's account of infinities has the shaky foundation of irrational numbers [Clegg] |
10869 | The Continuum Hypothesis is independent of the axioms of set theory [Clegg] |
10862 | The 'continuum hypothesis' says aleph-one is the cardinality of the reals [Clegg] |
13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
9240 | Love creates a necessity concerning what to care about [Frankfurt] |
9264 | Persons are distinguished by a capacity for second-order desires [Frankfurt] |
9266 | A person essentially has second-order volitions, and not just second-order desires [Frankfurt] |
9267 | Free will is the capacity to choose what sort of will you have [Frankfurt] |
9265 | The will is the effective desire which actually leads to an action [Frankfurt] |
20015 | Freedom of action needs the agent to identify with their reason for acting [Frankfurt, by Wilson/Schpall] |
9228 | Ranking order of desires reveals nothing, because none of them may be considered important [Frankfurt] |
9270 | A 'wanton' is not a person, because they lack second-order volitions [Frankfurt] |
9269 | A person may be morally responsible without free will [Frankfurt] |
9238 | Morality isn't based on reason; moral indignation is quite unlike disapproval of irrationality [Frankfurt] |
9232 | It is by caring about things that we infuse the world with importance [Frankfurt] |
9234 | If you don't care about at least one thing, you can't find reasons to care about anything [Frankfurt] |
9229 | What is worthwhile for its own sake alone may be worth very little [Frankfurt] |
9233 | Our criteria for evaluating how to live offer an answer to the problem [Frankfurt] |
9235 | Rather than loving things because we value them, I think we value things because we love them [Frankfurt] |
9236 | Love can be cool, and it may not involve liking its object [Frankfurt] |
9237 | The paradigm case of pure love is not romantic, but that between parents and infants [Frankfurt] |
9239 | I value my children for their sake, but I also value my love for them for its own sake [Frankfurt] |
9227 | We might not choose a very moral life, if the character or constitution was deficient [Frankfurt] |
9230 | People want to fulfill their desires, but also for their desires to be sustained [Frankfurt] |
9241 | Loving oneself is not a failing, but is essential to a successful life [Frankfurt] |
9300 | Boredom is serious, not just uncomfortable; it threatens our psychic survival [Frankfurt] |
9231 | Freedom needs autonomy (rather than causal independence) - embracing our own desires and choices [Frankfurt] |