69 ideas
20455 | Philosophy really got started as the rival mode of discourse to tragedy [Critchley] |
20446 | Philosophy begins in disappointment, notably in religion and politics [Critchley] |
6848 | Humour is practically enacted philosophy [Critchley] |
6847 | Humour can give a phenomenological account of existence, and point to change [Critchley] |
7068 | If infatuation with science leads to bad scientism, its rejection leads to obscurantism [Critchley] |
6844 | Scientism is the view that everything can be explained causally through scientific method [Critchley] |
20449 | Science gives us an excessively theoretical view of life [Critchley] |
7075 | To meet the division in our life, try the Subject, Nature, Spirit, Will, Power, Praxis, Unconscious, or Being [Critchley] |
7069 | The French keep returning, to Hegel or Nietzsche or Marx [Critchley] |
6835 | German idealism aimed to find a unifying principle for Kant's various dualisms [Critchley] |
6837 | Since Hegel, continental philosophy has been linked with social and historical enquiry. [Critchley] |
6836 | Continental philosophy fights the threatened nihilism in the critique of reason [Critchley] |
6838 | Continental philosophy is based on critique, praxis and emancipation [Critchley] |
6845 | Continental philosophy has a bad tendency to offer 'one big thing' to explain everything [Critchley] |
6846 | Phenomenology is a technique of redescription which clarifies our social world [Critchley] |
20448 | Phenomenology uncovers and redescribes the pre-theoretical layer of life [Critchley] |
10073 | There cannot be a set theory which is complete [Smith,P] |
10616 | Second-order arithmetic can prove new sentences of first-order [Smith,P] |
10075 | A 'partial function' maps only some elements to another set [Smith,P] |
10074 | A 'total function' maps every element to one element in another set [Smith,P] |
10612 | An argument is a 'fixed point' for a function if it is mapped back to itself [Smith,P] |
10076 | The 'range' of a function is the set of elements in the output set created by the function [Smith,P] |
10605 | Two functions are the same if they have the same extension [Smith,P] |
10615 | The Comprehension Schema says there is a property only had by things satisfying a condition [Smith,P] |
10595 | A 'theorem' of a theory is a sentence derived from the axioms using the proof system [Smith,P] |
10602 | A 'natural deduction system' has no axioms but many rules [Smith,P] |
10613 | No nice theory can define truth for its own language [Smith,P] |
10078 | An 'injective' ('one-to-one') function creates a distinct output element from each original [Smith,P] |
10077 | A 'surjective' ('onto') function creates every element of the output set [Smith,P] |
10079 | A 'bijective' function has one-to-one correspondence in both directions [Smith,P] |
10070 | If everything that a theory proves is true, then it is 'sound' [Smith,P] |
10086 | Soundness is true axioms and a truth-preserving proof system [Smith,P] |
10596 | A theory is 'sound' iff every theorem is true (usually from true axioms and truth-preservation) [Smith,P] |
10598 | A theory is 'negation complete' if it proves all sentences or their negation [Smith,P] |
10597 | 'Complete' applies both to whole logics, and to theories within them [Smith,P] |
10069 | A theory is 'negation complete' if one of its sentences or its negation can always be proved [Smith,P] |
10609 | Two routes to Incompleteness: semantics of sound/expressible, or syntax of consistency/proof [Smith,P] |
10080 | 'Effective' means simple, unintuitive, independent, controlled, dumb, and terminating [Smith,P] |
10087 | A theory is 'decidable' if all of its sentences could be mechanically proved [Smith,P] |
10088 | Any consistent, axiomatized, negation-complete formal theory is decidable [Smith,P] |
10081 | A set is 'enumerable' is all of its elements can result from a natural number function [Smith,P] |
10083 | A set is 'effectively enumerable' if a computer could eventually list every member [Smith,P] |
10084 | A finite set of finitely specifiable objects is always effectively enumerable (e.g. primes) [Smith,P] |
10085 | The set of ordered pairs of natural numbers <i,j> is effectively enumerable [Smith,P] |
10601 | The thorems of a nice arithmetic can be enumerated, but not the truths (so they're diffferent) [Smith,P] |
10600 | Being 'expressible' depends on language; being 'capture/represented' depends on axioms and proof system [Smith,P] |
10599 | For primes we write (x not= 1 ∧ ∀u∀v(u x v = x → (u = 1 ∨ v = 1))) [Smith,P] |
10610 | The reals contain the naturals, but the theory of reals doesn't contain the theory of naturals [Smith,P] |
10619 | The truths of arithmetic are just true equations and their universally quantified versions [Smith,P] |
10618 | All numbers are related to zero by the ancestral of the successor relation [Smith,P] |
10608 | The number of Fs is the 'successor' of the Gs if there is a single F that isn't G [Smith,P] |
10849 | Baby arithmetic covers addition and multiplication, but no general facts about numbers [Smith,P] |
10850 | Baby Arithmetic is complete, but not very expressive [Smith,P] |
10852 | Robinson Arithmetic (Q) is not negation complete [Smith,P] |
10851 | Robinson Arithmetic 'Q' has basic axioms, quantifiers and first-order logic [Smith,P] |
10068 | Natural numbers have zero, unique successors, unending, no circling back, and no strays [Smith,P] |
10603 | The logic of arithmetic must quantify over properties of numbers to handle induction [Smith,P] |
10848 | Multiplication only generates incompleteness if combined with addition and successor [Smith,P] |
10604 | Incompleteness results in arithmetic from combining addition and successor with multiplication [Smith,P] |
10617 | The 'ancestral' of a relation is a new relation which creates a long chain of the original relation [Smith,P] |
12887 | A whole must have one characteristic, an internal relation, and a structure [Rescher/Oppenheim] |
20454 | Wallace Stevens is the greatest philosophical poet of the twentieth century in English [Critchley] |
20456 | Interesting art is always organised around ethical demands [Critchley] |
20447 | The problems is not justifying ethics, but motivating it. Why should a self seek its good? [Critchley] |
7067 | Food first, then ethics [Critchley] |
6843 | Perceiving meaninglessness is an achievement, which can transform daily life [Critchley] |
20452 | Anarchism used to be libertarian (especially for sexuality), but now concerns responsibility [Critchley] |
20450 | The state, law, bureaucracy and capital are limitations on life, so I prefer federalist anarchism [Critchley] |
20451 | Belief that humans are wicked leads to authoritarian politics [Critchley] |