139 ideas
13466 | We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD] |
13477 | The problems are the monuments of philosophy [Hart,WD] |
13515 | To study abstract problems, some knowledge of set theory is essential [Hart,WD] |
19807 | Both nature and reason require that everything has a cause [Rousseau] |
13469 | Tarski showed how we could have a correspondence theory of truth, without using 'facts' [Hart,WD] |
13504 | Truth for sentences is satisfaction of formulae; for sentences, either all sequences satisfy it (true) or none do [Hart,WD] |
13503 | A first-order language has an infinity of T-sentences, which cannot add up to a definition of truth [Hart,WD] |
13500 | Conditional Proof: infer a conditional, if the consequent can be deduced from the antecedent [Hart,WD] |
13502 | ∃y... is read as 'There exists an individual, call it y, such that...', and not 'There exists a y such that...' [Hart,WD] |
13456 | Set theory articulates the concept of order (through relations) [Hart,WD] |
13497 | Nowadays ZFC and NBG are the set theories; types are dead, and NF is only useful for the whole universe [Hart,WD] |
13443 | ∈ relates across layers, while ⊆ relates within layers [Hart,WD] |
13442 | Without the empty set we could not form a∩b without checking that a and b meet [Hart,WD] |
13493 | In the modern view, foundation is the heart of the way to do set theory [Hart,WD] |
13495 | Foundation Axiom: an nonempty set has a member disjoint from it [Hart,WD] |
13461 | We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD] |
13462 | With the Axiom of Choice every set can be well-ordered [Hart,WD] |
13516 | If we accept that V=L, it seems to settle all the open questions of set theory [Hart,WD] |
13441 | Naïve set theory has trouble with comprehension, the claim that every predicate has an extension [Hart,WD] |
13494 | The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD] |
13457 | A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD] |
13490 | Von Neumann defines α<β as α∈β [Hart,WD] |
13458 | A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD] |
13460 | 'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD] |
13481 | Maybe sets should be rethought in terms of the even more basic categories [Hart,WD] |
9175 | We may fix the reference of 'Cicero' by a description, but thereafter the name is rigid [Kripke] |
9171 | The function of names is simply to refer [Kripke] |
13506 | The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD] |
13505 | Model theory studies how set theory can model sets of sentences [Hart,WD] |
13511 | Model theory is mostly confined to first-order theories [Hart,WD] |
13513 | Models are ways the world might be from a first-order point of view [Hart,WD] |
13512 | Modern model theory begins with the proof of Los's Conjecture in 1962 [Hart,WD] |
13496 | First-order logic is 'compact': consequences of a set are consequences of a finite subset [Hart,WD] |
13484 | Berry's Paradox: we succeed in referring to a number, with a term which says we can't do that [Hart,WD] |
13482 | The Burali-Forti paradox is a crisis for Cantor's ordinals [Hart,WD] |
13507 | The machinery used to solve the Liar can be rejigged to produce a new Liar [Hart,WD] |
13492 | Von Neumann's ordinals generalise into the transfinite better, because Zermelo's ω is a singleton [Hart,WD] |
13459 | The less-than relation < well-orders, and partially orders, and totally orders the ordinal numbers [Hart,WD] |
13463 | There are at least as many infinite cardinals as transfinite ordinals (because they will map) [Hart,WD] |
13491 | The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD] |
13446 | 19th century arithmetization of analysis isolated the real numbers from geometry [Hart,WD] |
13509 | We can establish truths about infinite numbers by means of induction [Hart,WD] |
13474 | Euclid has a unique parallel, spherical geometry has none, and saddle geometry has several [Hart,WD] |
13471 | Mathematics makes existence claims, but philosophers usually say those are never analytic [Hart,WD] |
13488 | Mass words do not have plurals, or numerical adjectives, or use 'fewer' [Hart,WD] |
9174 | It is necessary that this table is not made of ice, but we don't know it a priori [Kripke] |
9172 | A 'rigid designator' designates the same object in all possible worlds [Kripke] |
9173 | We cannot say that Nixon might have been a different man from the one he actually was [Kripke] |
9176 | Modal statements about this table never refer to counterparts; that confuses epistemology and metaphysics [Kripke] |
13480 | Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD] |
13476 | The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD] |
9177 | Identity theorists must deny that pains can be imagined without brain states [Kripke] |
9178 | Pain, unlike heat, is picked out by an essential property [Kripke] |
13475 | The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD] |
7235 | Without freedom of will actions lack moral significance [Rousseau] |
19791 | Natural mankind is too fragmented for states of peace, or of war and enmity [Rousseau] |
20501 | Rousseau assumes that laws need a people united by custom and tradition [Rousseau, by Wolff,J] |
7237 | The act of becoming 'a people' is the real foundation of society [Rousseau] |
19792 | To overcome obstacles, people must unite their forces into a single unified power [Rousseau] |
19812 | Human nature changes among a people, into a moral and partial existence [Rousseau] |
19814 | A state must be big enough to preserve itself, but small enough to be governable [Rousseau] |
19815 | Too much land is a struggle, producing defensive war; too little makes dependence, and offensive war [Rousseau] |
19822 | If the state enlarges, the creators of the general will become less individually powerful [Rousseau] |
19823 | If the population is larger, the government needs to be more powerful [Rousseau] |
7232 | Man is born free, and he is everywhere in chains [Rousseau] |
7234 | No man has any natural authority over his fellows [Rousseau] |
19816 | A state's purpose is liberty and equality - liberty for strength, and equality for liberty [Rousseau] |
7247 | The greatest social good comes down to freedom and equality [Rousseau] |
19838 | The measure of a successful state is increase in its population [Rousseau] |
19848 | The sovereignty does not appoint the leaders [Rousseau] |
20567 | Rousseau insists that popular sovereignty needs a means of expressing consent [Rousseau, by Oksala] |
19801 | Sovereignty is the exercise of the general will, which can never be delegated [Rousseau] |
19805 | Just as people control their limbs, the general-will state has total control of its members [Rousseau] |
19818 | Political laws are fundamental, as they firmly organise the state - but they could still be changed [Rousseau] |
19790 | Force can only dominate if it is seen as a right, and obedience as a duty [Rousseau] |
7233 | The social order is a sacred right, but based on covenants, not nature [Rousseau] |
19842 | The government is instituted by a law, not by a contract [Rousseau] |
7239 | The social pact is the total subjection of individuals to the general will [Rousseau] |
19793 | We need a protective association which unites forces, but retains individual freedom [Rousseau] |
7240 | To foreign powers a state is seen as a simple individual [Rousseau] |
19795 | The act of association commits citizens to the state, and the state to its citizens [Rousseau] |
19797 | Citizens must ultimately for forced to accept the general will (so freedom is compulsory!) [Rousseau] |
19796 | Individual citizens still retain a private will, which may be contrary to the general will [Rousseau] |
19808 | The general will changes its nature when it focuses on particulars [Rousseau] |
7246 | The general will is always good, but sometimes misunderstood [Rousseau] |
7250 | Laws are authentic acts of the general will [Rousseau] |
19844 | Assemblies must always confirm the form of government, and the current administration [Rousseau] |
19846 | The more unanimous the assembly, the stronger the general will becomes [Rousseau] |
7244 | The general will is common interest; the will of all is the sum of individual desires [Rousseau] |
19802 | The general will is always right, but the will of all can err, because it includes private interests [Rousseau] |
19804 | If a large knowledgeable population votes in isolation, their many choices will have good results [Rousseau] |
19803 | If the state contains associations there are fewer opinions, undermining the general will [Rousseau] |
19817 | Citizens should be independent of each other, and very dependent on the state [Rousseau] |
19840 | A citizen is a subject who is also sovereign [Rousseau] |
19839 | The flourishing of arts and letters is too much admired [Rousseau] |
19798 | Ancient monarchs were kings of peoples; modern monarchs more cleverly rule a land [Rousseau] |
19831 | The highest officers under a monarchy are normally useless; the public could choose much better [Rousseau] |
19833 | Hereditary monarchy is easier, but can lead to dreadful monarchs [Rousseau] |
19834 | Attempts to train future kings don't usually work, and the best have been unprepared [Rousseau] |
19829 | Natural aristocracy is primitive, and hereditary is dreadful, but elective aristocracy is best [Rousseau] |
7249 | Natural aristocracy is primitive, hereditary is bad, and elective aristocracy is the best [Rousseau] |
19830 | Large states need a nobility to fill the gap between a single prince and the people [Rousseau] |
19820 | The state has a legislature and an executive, just like the will and physical power in a person [Rousseau] |
19827 | Law makers and law implementers should be separate [Rousseau] |
19821 | I call the executive power the 'government', which is the 'prince' - a single person, or a group [Rousseau] |
19824 | Large populations needs stronger control, which means power should be concentrated [Rousseau] |
19826 | Democracy for small states, aristocracy for intermediate, monarchy for large [Rousseau] |
19837 | If inhabitants are widely dispersed, organising a revolt is much more difficult [Rousseau] |
19843 | The state is not bound to leave civil authority to its leaders [Rousseau] |
19825 | If the sovereign entrusts government to at least half the citizens, that is 'democracy' [Rousseau] |
19832 | Democratic elections are dangerous intervals in government [Rousseau] |
7243 | Silence of the people implies their consent [Rousseau] |
7251 | The English are actually slaves in between elections [Rousseau] |
7238 | Minorities only accept majority-voting because of a prior unanimous agreement [Rousseau] |
19828 | Democracy leads to internal strife, as people struggle to maintain or change ways of ruling [Rousseau] |
19835 | When ministers change the state changes, because they always reverse policies [Rousseau] |
19849 | In early theocracies the god was the king, and there were as many gods as nations [Rousseau] |
19841 | Sometimes full liberty is only possible at the expense of some complete enslavement [Rousseau] |
19847 | We can never assume that the son of a slave is a slave [Rousseau] |
7242 | Appetite alone is slavery, and self-prescribed laws are freedom [Rousseau] |
19800 | The social compact imposes conventional equality of rights on people who may start unequally [Rousseau] |
7248 | No citizen should be rich enough to buy another, and none so poor as forced to sell himself [Rousseau] |
19794 | If we all give up all of our rights together to the community, we will always support one another [Rousseau] |
7241 | In society man loses natural liberty, but gains a right to civil liberty and property [Rousseau] |
19806 | We alienate to society only what society needs - but society judges that, not us [Rousseau] |
19799 | Private property must always be subordinate to ownership by the whole community [Rousseau] |
19819 | The state ensures liberty, so civil law separates citizens, and binds them to the state [Rousseau] |
7245 | Natural justice, without sanctions, benefits the wicked, who exploit it [Rousseau] |
19810 | A trial proves that a criminal has broken the social treaty, and is no longer a member of the state [Rousseau] |
19809 | We accept the death penalty to prevent assassinations, so we must submit to it if necessary [Rousseau] |
19811 | Only people who are actually dangerous should be executed, even as an example [Rousseau] |
7236 | War gives no right to inflict more destruction than is necessary for victory [Rousseau] |
23607 | Wars are between States, not people, and the individuals are enemies by accident [Rousseau] |
19851 | Every society has a religion as its base [Rousseau] |
19850 | By separating theological and political systems, Jesus caused divisions in the state [Rousseau] |
19852 | Civil religion needs one supreme god, an afterlife, justice, and the sanctity of the social contract [Rousseau] |
19853 | All religions should be tolerated, if they tolerate each other, and support citizenship [Rousseau] |
19836 | The amount of taxation doesn't matter, if it quickly circulates back to the citizens [Rousseau] |
7252 | A tyrant exploits Christians because they don't value this life, and are made to be slaves [Rousseau] |