160 ideas
| 5196 | Philosophy is a department of logic [Ayer] |
| 5189 | Philosophers should abandon speculation, as philosophy is wholly critical [Ayer] |
| 7919 | Humeans rejected the a priori synthetic, and so rejected even Kantian metaphysics [Ayer, by Macdonald,C] |
| 5195 | Critics say analysis can only show the parts, and not their distinctive configuration [Ayer] |
| 5179 | Philosophy deals with the questions that scientists do not wish to handle [Ayer] |
| 19807 | Both nature and reason require that everything has a cause [Rousseau] |
| 4749 | We cannot analyse the concept of 'truth', because it is simply a mark that a sentence is asserted [Ayer] |
| 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] |
| 5202 | Maths and logic are true universally because they are analytic or tautological [Ayer] |
| 15928 | Intuitionism rejects set-theory to found mathematics [Lavine] |
| 6523 | Positivists regard ontology as either meaningless or stipulated [Ayer, by Robinson,H] |
| 5183 | Only tautologies can be certain; other propositions can only be probable [Ayer] |
| 6525 | Logical positivists could never give the sense-data equivalent of 'there is a table next door' [Robinson,H on Ayer] |
| 5170 | Material things are constructions from actual and possible occurrences of sense-contents [Ayer] |
| 5198 | We could verify 'a thing can't be in two places at once' by destroying one of the things [Ierubino on Ayer] |
| 2619 | Whether geometry can be applied to reality is an empirical question outside of geometry [Ayer] |
| 5197 | By changing definitions we could make 'a thing can't be in two places at once' a contradiction [Ayer] |
| 5204 | To say that a proposition is true a priori is to say that it is a tautology [Ayer] |
| 6524 | Positivists prefer sense-data to objects, because the vocabulary covers both illusions and perceptions [Ayer, by Robinson,H] |
| 5193 | Causal and representative theories of perception are wrong as they refer to unobservables [Ayer] |
| 5200 | The main claim of rationalism is that thought is an independent source of knowledge [Ayer] |
| 4729 | Empiricism lacked a decent account of the a priori, until Ayer said it was entirely analytic [O'Grady on Ayer] |
| 5180 | All propositions (especially 'metaphysics') must begin with the senses [Ayer] |
| 5169 | My empiricism logically distinguishes analytic and synthetic propositions, and metaphysical verbiage [Ayer] |
| 5185 | It is further sense-experience which informs us of the mistakes that arise out of sense-experience [Ayer] |
| 5199 | Empiricism, it is said, cannot account for our knowledge of necessary truths [Ayer] |
| 5190 | The induction problem is to prove generalisations about the future based on the past [Ayer] |
| 5191 | We can't use the uniformity of nature to prove induction, as that would be circular [Ayer] |
| 5177 | Other minds are 'metaphysical' objects, because I can never observe their experiences [Ayer] |
| 5178 | A conscious object is by definition one that behaves in a certain way, so behaviour proves consciousness [Ayer] |
| 5172 | If the self is meaningful, it must be constructed from sense-experiences [Ayer] |
| 5173 | Two experiences belong to one self if their contents belong with one body [Ayer] |
| 5176 | Empiricists can define personal identity as bodily identity, which consists of sense-contents [Ayer] |
| 5171 | The supposed 'gulf' between mind and matter is based on the senseless concept of 'substances' [Ayer] |
| 5181 | A sentence is factually significant to someone if they know how to verify its proposition [Ayer] |
| 5184 | Factual propositions imply (in conjunction with a few other premises) possible experiences [Ayer] |
| 5186 | Tautologies and empirical hypotheses form the entire class of significant propositions [Ayer] |
| 7235 | Without freedom of will actions lack moral significance [Rousseau] |
| 5205 | Moral intuition is worthless if there is no criterion to decide between intuitions [Ayer] |
| 23725 | Ayer defends the emotivist version of expressivism [Ayer, by Smith,M] |
| 5206 | To say an act is wrong makes no further statement about it, but merely expresses disapproval [Ayer] |
| 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] |
| 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] |
| 19803 | If the state contains associations there are fewer opinions, undermining the general will [Rousseau] |
| 19804 | If a large knowledgeable population votes in isolation, their many choices will have good results [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] |
| 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] |
| 19827 | Law makers and law implementers should be separate [Rousseau] |
| 19820 | The state has a legislature and an executive, just like the will and physical power in a person [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] |
| 19809 | We accept the death penalty to prevent assassinations, so we must submit to it if necessary [Rousseau] |
| 19810 | A trial proves that a criminal has broken the social treaty, and is no longer a member of the state [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] |
| 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] |
| 19851 | Every society has a religion as its base [Rousseau] |
| 19836 | The amount of taxation doesn't matter, if it quickly circulates back to the citizens [Rousseau] |
| 5208 | A person with non-empirical attributes is unintelligible. [Ayer] |
| 5187 | When we ascribe an attribute to a thing, we covertly assert that it exists [Ayer] |
| 5207 | If theism is non-sensical, then so is atheism. [Ayer] |
| 7252 | A tyrant exploits Christians because they don't value this life, and are made to be slaves [Rousseau] |
| 5209 | The 'truths' expressed by theists are not literally significant [Ayer] |