54 ideas
18996 | A statement S is 'partly true' if it has some wholly true parts [Yablo] |
19006 | An 'enthymeme' is an argument with an indispensable unstated assumption [Yablo] |
17749 | Post proved the consistency of propositional logic in 1921 [Walicki] |
17765 | Propositional language can only relate statements as the same or as different [Walicki] |
17764 | Boolean connectives are interpreted as functions on the set {1,0} [Walicki] |
8859 | The main modal logics disagree over three key formulae [Yablo] |
17752 | The empty set is useful for defining sets by properties, when the members are not yet known [Walicki] |
17753 | The empty set avoids having to take special precautions in case members vanish [Walicki] |
17759 | Ordinals play the central role in set theory, providing the model of well-ordering [Walicki] |
18999 | y is only a proper part of x if there is a z which 'makes up the difference' between them [Yablo] |
17741 | To determine the patterns in logic, one must identify its 'building blocks' [Walicki] |
19001 | 'Pegasus doesn't exist' is false without Pegasus, yet the absence of Pegasus is its truthmaker [Yablo] |
17747 | A 'model' of a theory specifies interpreting a language in a domain to make all theorems true [Walicki] |
17748 | The L-S Theorem says no theory (even of reals) says more than a natural number theory [Walicki] |
17761 | A compact axiomatisation makes it possible to understand a field as a whole [Walicki] |
17763 | Axiomatic systems are purely syntactic, and do not presuppose any interpretation [Walicki] |
9138 | An infinite series of sentences asserting falsehood produces the paradox without self-reference [Yablo, by Sorensen] |
8865 | If 'the number of Democrats is on the rise', does that mean that 50 million is on the rise? [Yablo] |
17757 | Members of ordinals are ordinals, and also subsets of ordinals [Walicki] |
17755 | Ordinals are the empty set, union with the singleton, and any arbitrary union of ordinals [Walicki] |
17756 | The union of finite ordinals is the first 'limit ordinal'; 2ω is the second... [Walicki] |
17760 | Two infinite ordinals can represent a single infinite cardinal [Walicki] |
17758 | Ordinals are transitive sets of transitive sets; or transitive sets totally ordered by inclusion [Walicki] |
17762 | In non-Euclidean geometry, all Euclidean theorems are valid that avoid the fifth postulate [Walicki] |
17754 | Inductive proof depends on the choice of the ordering [Walicki] |
19002 | A nominalist can assert statements about mathematical objects, as being partly true [Yablo] |
8863 | We must treat numbers as existing in order to express ourselves about the arrangement of planets [Yablo] |
10580 | Mathematics is both necessary and a priori because it really consists of logical truths [Yablo] |
8862 | Platonic objects are really created as existential metaphors [Yablo] |
10579 | Putting numbers in quantifiable position (rather than many quantifiers) makes expression easier [Yablo] |
10577 | Concrete objects have few essential properties, but properties of abstractions are mostly essential [Yablo] |
10578 | We are thought to know concreta a posteriori, and many abstracta a priori [Yablo] |
19489 | For me, fictions are internally true, without a significant internal or external truth-value [Yablo] |
19490 | Make-believe can help us to reason about facts and scientific procedures [Yablo] |
19491 | 'The clouds are angry' can only mean '...if one were attributing emotions to clouds' [Yablo] |
8864 | We quantify over events, worlds, etc. in order to make logical possibilities clearer [Yablo] |
19494 | Fictionalism allows that simulated beliefs may be tracking real facts [Yablo] |
8858 | Philosophers keep finding unexpected objects, like models, worlds, functions, numbers, events, sets, properties [Yablo] |
14381 | A statue is essentially the statue, but its lump is not essentially a statue, so statue isn't lump [Yablo, by Rocca] |
18998 | Parthood lacks the restriction of kind which most relations have [Yablo] |
17742 | Scotus based modality on semantic consistency, instead of on what the future could allow [Walicki] |
19493 | Governing possible worlds theory is the fiction that if something is possible, it happens in a world [Yablo] |
19004 | Gettier says you don't know if you are confused about how it is true [Yablo] |
19007 | A theory need not be true to be good; it should just be true about its physical aspects [Yablo] |
18993 | If sentences point to different evidence, they must have different subject-matter [Yablo] |
19003 | Most people say nonblack nonravens do confirm 'all ravens are black', but only a tiny bit [Yablo] |
10805 | A sentence should be recarved to reveal its content or implication relations [Yablo] |
18992 | Sentence-meaning is the truth-conditions - plus factors responsible for them [Yablo] |
18994 | The content of an assertion can be quite different from compositional content [Yablo] |
18997 | Truth-conditions as subject-matter has problems of relevance, short cut, and reversal [Yablo] |
19005 | Not-A is too strong to just erase an improper assertion, because it actually reverses A [Yablo] |
8861 | Hardly a word in the language is devoid of metaphorical potential [Yablo] |
20579 | Modern totalitarianism results from lack of social ties or shared goals [Arendt, by Oksala] |
20580 | The ideal subject for dictators is not a fanatic, but someone who can't distinguish true from false [Arendt, by Oksala] |