36 ideas
1815 | Reasoning needs arbitrary faith in preliminary hypotheses (Mode 14) [Agrippa, by Diog. Laertius] |
1812 | All discussion is full of uncertainty and contradiction (Mode 11) [Agrippa, by Diog. Laertius] |
1811 | Proofs often presuppose the thing to be proved (Mode 15) [Agrippa, by Diog. Laertius] |
1813 | All reasoning endlessly leads to further reasoning (Mode 12) [Agrippa, by Diog. Laertius] |
4901 | Truth has to be correspondence to facts, and a match between relations of ideas and relations in the world [Perry] |
13913 | The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward] |
13914 | Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward] |
13915 | Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward] |
13916 | Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward] |
13850 | In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward] |
13849 | Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward] |
13851 | Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward] |
13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
4885 | Identity is a very weak relation, which doesn't require interdefinability, or shared properties [Perry] |
12155 | Statements of 'relative identity' are really statements of resemblance [Perry] |
4899 | Possible worlds thinking has clarified the logic of modality, but is problematic in epistemology [Perry] |
4898 | Possible worlds are indices for a language, or concrete realities, or abstract possibilities [Perry] |
12149 | Indexicals are a problem for beliefs being just subject-proposition relations [Perry] |
8850 | Agrippa's Trilemma: justification is infinite, or ends arbitrarily, or is circular [Agrippa, by Williams,M] |
1814 | Everything is perceived in relation to another thing (Mode 13) [Agrippa, by Diog. Laertius] |
4887 | We try to cause other things to occur by causing mental events to occur [Perry] |
4884 | Brain states must be in my head, and yet the pain seems to be in my hand [Perry] |
4888 | It seems plausible that many animals have experiences without knowing about them [Perry] |
4891 | If epiphenomenalism just says mental events are effects but not causes, it is consistent with physicalism [Perry] |
4900 | Prior to Kripke, the mind-brain identity theory usually claimed that the identity was contingent [Perry] |
4892 | If physicalists stick with identity (not supervenience), Martian pain will not be like ours [Perry] |
16391 | Indexical thoughts are about themselves, and ascribe properties to themselves [Perry, by Recanati] |
4889 | Although we may classify ideas by content, we individuate them differently, as their content can change [Perry] |
4896 | The intension of an expression is a function from possible worlds to an appropriate extension [Perry] |
12151 | If we replace 'I' in sentences about me, they are different beliefs and explanations of behaviour [Perry] |
18412 | Indexicals individuate certain belief states, helping in explanation and prediction [Perry] |
4897 | A proposition is a set of possible worlds for which its intension delivers truth [Perry] |
12150 | Indexicals reveal big problems with the traditional idea of a proposition [Perry] |
4890 | A sharp analytic/synthetic line can rarely be drawn, but some concepts are central to thought [Perry] |
15203 | Tense is essential for thought and action [Perry, by Le Poidevin] |
15204 | Actual tensed sentences cannot be tenseless, because they can cite their own context [Perry, by Le Poidevin] |