69 ideas
6200 | Wisdom is knowing the highest good, and conforming the will to it [Kant] |
6207 | What fills me with awe are the starry heavens above me and the moral law within me [Kant] |
6184 | Consistency is the highest obligation of a philosopher [Kant] |
6203 | Metaphysics is just a priori universal principles of physics [Kant] |
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] |
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] |
6181 | Necessity cannot be extracted from an empirical proposition [Kant] |
6183 | Can pure reason determine the will, or are empirical conditions relevant? [Kant] |
6191 | The will is the faculty of purposes, which guide desires according to principles [Kant] |
6190 | The sole objects of practical reason are the good and the evil [Kant] |
18235 | Only human reason can confer value on our choices [Kant, by Korsgaard] |
6196 | People cannot come to morality through feeling, because morality must not be sensuous [Kant] |
18675 | Kant may rate two things as finally valuable: having a good will, and deserving happiness [Orsi on Kant] |
22007 | An autonomous agent has dignity [Würde], which has absolute worth [Kant, by Pinkard] |
18234 | The good will is unconditionally good, because it is the only possible source of value [Kant, by Korsgaard] |
6192 | Good or evil cannot be a thing, but only a maxim of action, making the person good or evil [Kant] |
6197 | Morality involves duty and respect for law, not love of the outcome [Kant] |
6193 | Our happiness is all that matters, not as a sensation, but as satisfaction with our whole existence [Kant] |
1452 | Happiness is the condition of a rational being for whom everything goes as they wish [Kant] |
1454 | Morality is not about making ourselves happy, but about being worthy of happiness [Kant] |
6194 | The highest worth for human beings lies in dispositions, not just actions [Kant] |
6198 | Virtue is the supreme state of our pursuit of happiness, and so is supreme good [Kant] |
1456 | Moral law is holy, and the best we can do is achieve virtue through respect for the law [Kant] |
6185 | No one would lend money unless a universal law made it secure, even after death [Kant] |
6187 | Universality determines the will, and hence extends self-love into altruism [Kant] |
6201 | Everyone (even God) must treat rational beings as ends in themselves, and not just as means [Kant] |
6186 | A holy will is incapable of any maxims which conflict with the moral law [Kant] |
6195 | Reason cannot solve the problem of why a law should motivate the will [Kant] |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
6188 | A permanent natural order could not universalise a rule permitting suicide [Kant] |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
6199 | Obligation does not rest on the existence of God, but on the autonomy of reason [Kant] |
1453 | We have to postulate something outside nature which makes happiness coincide with morality [Kant] |
1455 | Belief in justice requires belief in a place for justice (heaven), a time (eternity), and a cause (God) [Kant, by PG] |
6205 | To know if this world must have been created by God, we would need to know all other possible worlds [Kant] |
6204 | Using God to explain nature is referring to something inconceivable to explain what is in front of you [Kant] |
6206 | From our limited knowledge we can infer great virtues in God, but not ultimate ones [Kant] |
6202 | In all naturalistic concepts of God, if you remove the human qualities there is nothing left [Kant] |