68 ideas
| 1922 | Spiritual qualities only become advantageous with the growth of wisdom [Plato] |
| 23770 | Reductive analysis makes a concept clearer, by giving an alternative simpler set [Williams,NE] |
| 23769 | Promoting an ontology by its implied good metaphysic is an 'argument-by-display' [Williams,NE] |
| 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] |
| 15934 | Mathematical proof by contradiction needs the law of excluded middle [Lavine] |
| 11259 | How can you seek knowledge of something if you don't know it? [Plato] |
| 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] |
| 23783 | Change exists, it is causal, and it needs an explanation [Williams,NE] |
| 23784 | Processes don't begin or end; they just change direction unexpectedly [Williams,NE] |
| 23790 | Processes are either strings of short unchanging states, or continuous and unreducible events [Williams,NE] |
| 23786 | The status quo is part of what exists, and so needs metaphysical explanation [Williams,NE] |
| 23768 | A metaphysic is a set of wider explanations derived from a basic ontology [Williams,NE] |
| 23773 | Humeans say properties are passive, possibility is vast, laws are descriptions, causation is weak [Williams,NE] |
| 23779 | We shouldn't posit the existence of anything we have a word for [Williams,NE] |
| 23775 | Powers are 'multi-track' if they can produce a variety of manifestations [Williams,NE] |
| 23780 | Every possible state of affairs is written into its originating powers [Williams,NE] |
| 23789 | Naming powers is unwise, because that it usually done by a single manifestation [Williams,NE] |
| 23771 | Fundamental physics describes everything in terms of powers [Williams,NE] |
| 23776 | Rather than pure powers or pure categoricals, I favour basics which are both at once [Williams,NE] |
| 23777 | Powers are more complicated than properties which are always on display [Williams,NE] |
| 23774 | There are basic powers, which underlie dispositions, potentialities, capacities etc [Williams,NE] |
| 23791 | Dispositions are just useful descriptions, which are explained by underlying powers [Williams,NE] |
| 23772 | If objects are property bundles, the properties need combining powers [Williams,NE] |
| 23788 | Four-Dimensional is Perdurantism (temporal parts), plus Eternalism [Williams,NE] |
| 20219 | True opinions only become really valuable when they are tied down by reasons [Plato] |
| 5985 | Seeking and learning are just recollection [Plato] |
| 5986 | The slave boy learns geometry from questioning, not teaching, so it is recollection [Plato] |
| 1923 | As a guide to action, true opinion is as good as knowledge [Plato] |
| 1919 | You don't need to learn what you know, and how do you seek for what you don't know? [Plato] |
| 1927 | It seems that virtue is neither natural nor taught, but is a divine gift [Plato] |
| 1913 | Is virtue taught, or achieved by practice, or a natural aptitude, or what? [Plato] |
| 1921 | If virtue is a type of knowledge then it ought to be taught [Plato] |
| 1916 | Even if virtues are many and various, they must have something in common to make them virtues [Plato] |
| 1918 | How can you know part of virtue without knowing the whole? [Plato] |
| 23785 | Causation needs to explain stasis, as well as change [Williams,NE] |
| 23782 | Causation is the exercise of powers [Williams,NE] |
| 23787 | If causes and effects overlap, that makes changes impossible [Williams,NE] |
| 23778 | Powers contain lawlike features, pointing to possible future states [Williams,NE] |