64 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] |
4643 | The Principle of Sufficient Reason does not presuppose that all explanations will be causal explanations [Baggini /Fosl] |
4633 | You cannot rationally deny the principle of non-contradiction, because all reasoning requires it [Baggini /Fosl] |
4635 | Dialectic aims at unified truth, unlike analysis, which divides into parts [Baggini /Fosl] |
4749 | We cannot analyse the concept of 'truth', because it is simply a mark that a sentence is asserted [Ayer] |
4632 | 'Natural' systems of deduction are based on normal rational practice, rather than on axioms [Baggini /Fosl] |
4631 | In ideal circumstances, an axiom should be such that no rational agent could possibly object to its use [Baggini /Fosl] |
4638 | The principle of bivalence distorts reality, as when claiming that a person is or is not 'thin' [Baggini /Fosl] |
5202 | Maths and logic are true universally because they are analytic or tautological [Ayer] |
6523 | Positivists regard ontology as either meaningless or stipulated [Ayer, by Robinson,H] |
4640 | If identity is based on 'true of X' instead of 'property of X' we get the Masked Man fallacy ('I know X but not Y') [Baggini /Fosl, by PG] |
4647 | 'I have the same car as you' is fine; 'I have the same fiancée as you' is not so good [Baggini /Fosl] |
4639 | Leibniz's Law is about the properties of objects; the Identity of Indiscernibles is about perception of objects [Baggini /Fosl] |
4646 | Is 'events have causes' analytic a priori, synthetic a posteriori, or synthetic a priori? [Baggini /Fosl] |
12899 | The timid student has knowledge without belief, lacking confidence in their correct answer [Lewis] |
5183 | Only tautologies can be certain; other propositions can only be probable [Ayer] |
12897 | To say S knows P, but cannot eliminate not-P, sounds like a contradiction [Lewis] |
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] |
4645 | 'A priori' does not concern how you learn a proposition, but how you show whether it is true or false [Baggini /Fosl] |
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] |
12898 | Justification is neither sufficient nor necessary for knowledge [Lewis] |
4582 | Basic beliefs are self-evident, or sensual, or intuitive, or revealed, or guaranteed [Baggini /Fosl] |
12895 | Knowing is context-sensitive because the domain of quantification varies [Lewis, by Cohen,S] |
19562 | We have knowledge if alternatives are eliminated, but appropriate alternatives depend on context [Lewis, by Cohen,S] |
4644 | A proposition such as 'some swans are purple' cannot be falsified, only verified [Baggini /Fosl] |
4584 | The problem of induction is how to justify our belief in the uniformity of nature [Baggini /Fosl] |
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] |
4583 | How can an argument be good induction, but poor deduction? [Baggini /Fosl] |
4634 | Abduction aims at simplicity, testability, coherence and comprehensiveness [Baggini /Fosl] |
4637 | To see if an explanation is the best, it is necessary to investigate the alternative explanations [Baggini /Fosl] |
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] |
4629 | Consistency is the cornerstone of rationality [Baggini /Fosl] |
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] |
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] |
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] |
5209 | The 'truths' expressed by theists are not literally significant [Ayer] |