81 ideas
19073 | True philosophy aims at absolute unity, while our understanding sees only separation [Hegel] |
15624 | Free thinking has no presuppositions [Hegel] |
15631 | The ideal of reason is the unification of abstract identity (or 'concept') and being [Hegel] |
15612 | Older metaphysics naively assumed that thought grasped things in themselves [Hegel] |
21768 | Logic is metaphysics, the science of things grasped in thoughts [Hegel] |
21984 | We must break up the rigidity that our understanding has imposed [Hegel] |
22081 | Let thought follow its own course, and don't interfere [Hegel] |
15626 | Categories create objective experience, but are too conditioned by things to actually grasp them [Hegel] |
15616 | If truth is just non-contradiction, we must take care that our basic concepts aren't contradictory [Hegel] |
15615 | Older metaphysics became dogmatic, by assuming opposed assertions must be true and false [Hegel] |
21767 | Dialectic is seen in popular proverbs like 'pride comes before a fall' [Hegel] |
15638 | Dialectic is the moving soul of scientific progression, the principle which binds science together [Hegel] |
15639 | Socratic dialectic is subjective, but Plato made it freely scientific and objective [Hegel] |
19070 | Superficial truth is knowing how something is, which is consciousness of bare correctness [Hegel] |
5644 | In Hegel's logic it is concepts (rather than judgements or propositions) which are true or false [Hegel, by Scruton] |
19072 | In the deeper sense of truth, to be untrue resembles being bad; badness is untrue to a thing's nature [Hegel] |
19071 | The deeper sense of truth is a thing matching the idea of what it ought to be [Hegel] |
15945 | Second-order set theory just adds a version of Replacement that quantifies over functions [Lavine] |
15914 | An 'upper bound' is the greatest member of a subset; there may be several of these, so there is a 'least' one [Lavine] |
15921 | Collections of things can't be too big, but collections by a rule seem unlimited in size [Lavine] |
15937 | Those who reject infinite collections also want to reject the Axiom of Choice [Lavine] |
15936 | The Power Set is just the collection of functions from one collection to another [Lavine] |
15899 | Replacement was immediately accepted, despite having very few implications [Lavine] |
15930 | Foundation says descending chains are of finite length, blocking circularity, or ungrounded sets [Lavine] |
15920 | Pure collections of things obey Choice, but collections defined by a rule may not [Lavine] |
15898 | The controversy was not about the Axiom of Choice, but about functions as arbitrary, or given by rules [Lavine] |
15919 | The 'logical' notion of class has some kind of definition or rule to characterise the class [Lavine] |
15900 | The iterative conception of set wasn't suggested until 1947 [Lavine] |
15931 | The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine] |
15932 | The iterative conception doesn't unify the axioms, and has had little impact on mathematical proofs [Lavine] |
15933 | Limitation of Size: if it's the same size as a set, it's a set; it uses Replacement [Lavine] |
15913 | A collection is 'well-ordered' if there is a least element, and all of its successors can be identified [Lavine] |
15926 | Second-order logic presupposes a set of relations already fixed by the first-order domain [Lavine] |
21595 | Excluded middle is the maxim of definite understanding, but just produces contradictions [Hegel] |
15934 | Mathematical proof by contradiction needs the law of excluded middle [Lavine] |
15628 | The idea that contradiction is essential to rational understanding is a key modern idea [Hegel] |
15629 | Tenderness for the world solves the antinomies; contradiction is in our reason, not in the essence of the world [Hegel] |
15630 | Antinomies are not just in four objects, but in all objects, all representations, all objects and all ideas [Hegel] |
15907 | Mathematics is nowadays (thanks to set theory) regarded as the study of structure, not of quantity [Lavine] |
15942 | Every rational number, unlike every natural number, is divisible by some other number [Lavine] |
15922 | For the real numbers to form a set, we need the Continuum Hypothesis to be true [Lavine] |
18250 | Cauchy gave a necessary condition for the convergence of a sequence [Lavine] |
15904 | The two sides of the Cut are, roughly, the bounding commensurable ratios [Lavine] |
15912 | Counting results in well-ordering, and well-ordering makes counting possible [Lavine] |
15949 | The theory of infinity must rest on our inability to distinguish between very large sizes [Lavine] |
15947 | The infinite is extrapolation from the experience of indefinitely large size [Lavine] |
15940 | The intuitionist endorses only the potential infinite [Lavine] |
15909 | 'Aleph-0' is cardinality of the naturals, 'aleph-1' the next cardinal, 'aleph-ω' the ω-th cardinal [Lavine] |
15915 | Ordinals are basic to Cantor's transfinite, to count the sets [Lavine] |
15917 | Paradox: the class of all ordinals is well-ordered, so must have an ordinal as type - giving a bigger ordinal [Lavine] |
15918 | Paradox: there is no largest cardinal, but the class of everything seems to be the largest [Lavine] |
15929 | Set theory will found all of mathematics - except for the notion of proof [Lavine] |
15935 | Modern mathematics works up to isomorphism, and doesn't care what things 'really are' [Lavine] |
15928 | Intuitionism rejects set-theory to found mathematics [Lavine] |
22078 | Even simple propositions about sensations are filled with categories [Hegel] |
15634 | Thought about particulars is done entirely through categories [Hegel] |
21981 | The one substance is formless without the mediation of dialectical concepts [Hegel] |
15637 | Essence is the essential self-positing unity of immediacy and mediation [Hegel] |
15613 | Real cognition grasps a thing from within itself, and is not satisfied with mere predicates [Hegel] |
15636 | The Cogito is at the very centre of the entire concern of modern philosophy [Hegel] |
22300 | Existence is just a set of relationships [Hegel] |
15609 | The sensible is distinguished from thought by being about singular things [Hegel] |
15625 | Sense perception is secondary and dependent, while thought is independent and primitive [Hegel] |
15619 | Empiricism made particular knowledge possible, and blocked wild claims [Hegel] |
15620 | Empiricism contains the important idea that we should see knowledge for ourselves, and be part of it [Hegel] |
15622 | Empiricism unknowingly contains and uses a metaphysic, which underlies its categories [Hegel] |
15621 | Empiricism of the finite denies the supersensible, and can only think with formal abstraction [Hegel] |
15632 | The Humean view stops us thinking about perception, and finding universals and necessities in it [Hegel] |
15623 | Humean scepticism, unlike ancient Greek scepticism, accepts the truth of experience as basic [Hegel] |
15617 | In abstraction, beyond finitude, freedom and necessity must exist together [Hegel] |
15608 | The act of thinking is the bringing forth of universals [Hegel] |
21986 | Hegel's system has a vast number of basic concepts [Hegel, by Moore,AW] |
15607 | We don't think with concepts - we think the concepts [Hegel] |
15610 | Active thought about objects produces the universal, which is what is true and essential of it [Hegel] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
15614 | Old metaphysics tried to grasp eternal truths through causal events, which is impossible [Hegel] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
15635 | The older conception of God was emptied of human features, to make it worthy of the Infinite [Hegel] |
21980 | God is the absolute thing, and also the absolute person [Hegel] |
15618 | If God is the abstract of Supremely Real Essence, then God is a mere Beyond, and unknowable [Hegel] |
15633 | We establish unification of the Ideal by the ontological proof, deriving being from abstraction of thinking [Hegel] |