62 ideas
7490 | Because of Darwin, wisdom as a definite attainable state has faded [Watson] |
7461 | The three key ideas are the soul, Europe, and the experiment [Watson] |
7464 | The big idea: imitation, the soul, experiments, God, heliocentric universe, evolution? [Watson] |
7465 | Babylonian thinking used analogy, rather than deduction or induction [Watson] |
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] |
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] |
7466 | Mesopotamian numbers applied to specific things, and then became abstract [Watson] |
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] |
7357 | People who control others with fluent language often end up being hated [Kongzi (Confucius)] |
7358 | All men prefer outward appearance to true excellence [Kongzi (Confucius)] |
7362 | Humans are similar, but social conventions drive us apart (sages and idiots being the exceptions) [Kongzi (Confucius)] |
7360 | Do not do to others what you would not desire yourself [Kongzi (Confucius)] |
7359 | Excess and deficiency are equally at fault [Kongzi (Confucius)] |
7363 | The virtues of the best people are humility, maganimity, sincerity, diligence, and graciousness [Kongzi (Confucius)] |
7361 | Men of the highest calibre avoid political life completely [Kongzi (Confucius)] |
23393 | Confucianism assumes that all good developments have happened, and there is only one Way [Norden on Kongzi (Confucius)] |
7477 | Modern democracy is actually elective oligarchy [Watson] |
7478 | Greek philosophers invented the concept of 'nature' as their special subject [Watson] |
7462 | DNA mutation suggests humans and chimpanzees diverged 6.6 million years ago [Watson] |
7470 | During the rise of civilizations, the main gods changed from female to male [Watson] |
7474 | Hinduism has no founder, or prophet, or creed, or ecclesiastical structure [Watson] |
7479 | Modern Judaism became stabilised in 200 CE [Watson] |
7481 | The Israelites may have asserted the uniqueness of Yahweh to justify land claims [Watson] |
7480 | Monotheism was a uniquely Israelite creation within the Middle East [Watson] |
7471 | The Gathas (hymns) of Zoroastrianism date from about 1000 BCE [Watson] |
7473 | Zoroaster conceived the afterlife, judgement, heaven and hell, and the devil [Watson] |
7484 | Jesus never intended to start a new religion [Watson] |
7483 | Paul's early writings mention few striking episodes from Jesus' life [Watson] |
7475 | Confucius revered the spiritual world, but not the supernatural, or a personal god, or the afterlife [Watson] |
7476 | Taoism aims at freedom from the world, the body, the mind, and nature [Watson] |
7463 | The three basic ingredients of religion are: the soul, seers or priests, and ritual [Watson] |
7468 | In ancient Athens the souls of the dead are received by the 'upper air' [Watson] |