52 ideas
9136 | The paradox of analysis says that any conceptual analysis must be either trivial or false [Sorensen] |
9131 | Two long understandable sentences can have an unintelligible conjunction [Sorensen] |
9139 | If nothing exists, no truthmakers could make 'Nothing exists' true [Sorensen] |
9140 | Which toothbrush is the truthmaker for 'buy one, get one free'? [Sorensen] |
10482 | The logic of ZF is classical first-order predicate logic with identity [Boolos] |
10492 | A few axioms of set theory 'force themselves on us', but most of them don't [Boolos] |
18192 | Do the Replacement Axioms exceed the iterative conception of sets? [Boolos, by Maddy] |
7785 | The use of plurals doesn't commit us to sets; there do not exist individuals and collections [Boolos] |
10485 | Naïve sets are inconsistent: there is no set for things that do not belong to themselves [Boolos] |
10484 | The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos] |
13547 | Limitation of Size is weak (Fs only collect is something the same size does) or strong (fewer Fs than objects) [Boolos, by Potter] |
10699 | Does a bowl of Cheerios contain all its sets and subsets? [Boolos] |
14249 | Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley] |
10225 | Monadic second-order logic might be understood in terms of plural quantifiers [Boolos, by Shapiro] |
10830 | Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos] |
10736 | Boolos showed how plural quantifiers can interpret monadic second-order logic [Boolos, by Linnebo] |
10780 | Any sentence of monadic second-order logic can be translated into plural first-order logic [Boolos, by Linnebo] |
10829 | A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos] |
9119 | No attempt to deny bivalence has ever been accepted [Sorensen] |
10697 | Identity is clearly a logical concept, and greatly enhances predicate calculus [Boolos] |
9135 | We now see that generalizations use variables rather than abstract entities [Sorensen] |
10832 | '∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos] |
13671 | Second-order quantifiers are just like plural quantifiers in ordinary language, with no extra ontology [Boolos, by Shapiro] |
10267 | We should understand second-order existential quantifiers as plural quantifiers [Boolos, by Shapiro] |
10698 | Plural forms have no more ontological commitment than to first-order objects [Boolos] |
7806 | Boolos invented plural quantification [Boolos, by Benardete,JA] |
10834 | Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos] |
13841 | Why should compactness be definitive of logic? [Boolos, by Hacking] |
9125 | Denying problems, or being romantically defeated by them, won't make them go away [Sorensen] |
9137 | Banning self-reference would outlaw 'This very sentence is in English' [Sorensen] |
10491 | Infinite natural numbers is as obvious as infinite sentences in English [Boolos] |
10483 | Mathematics and science do not require very high orders of infinity [Boolos] |
10833 | Many concepts can only be expressed by second-order logic [Boolos] |
10490 | Mathematics isn't surprising, given that we experience many objects as abstract [Boolos] |
9116 | Vague words have hidden boundaries [Sorensen] |
10700 | First- and second-order quantifiers are two ways of referring to the same things [Boolos] |
10488 | It is lunacy to think we only see ink-marks, and not word-types [Boolos] |
10487 | I am a fan of abstract objects, and confident of their existence [Boolos] |
10489 | We deal with abstract objects all the time: software, poems, mistakes, triangles.. [Boolos] |
9132 | An offer of 'free coffee or juice' could slowly shift from exclusive 'or' to inclusive 'or' [Sorensen] |
9128 | It is propositional attitudes which can be a priori, not the propositions themselves [Sorensen] |
9130 | Attributing apriority to a proposition is attributing a cognitive ability to someone [Sorensen] |
9118 | The colour bands of the spectrum arise from our biology; they do not exist in the physics [Sorensen] |
9124 | We are unable to perceive a nose (on the back of a mask) as concave [Sorensen] |
9126 | Bayesians build near-certainty from lots of reasonably probable beliefs [Sorensen] |
9121 | Illusions are not a reason for skepticism, but a source of interesting scientific information [Sorensen] |
8693 | An 'abstraction principle' says two things are identical if they are 'equivalent' in some respect [Boolos] |
9134 | The negation of a meaningful sentence must itself be meaningful [Sorensen] |
9133 | Propositions are what settle problems of ambiguity in sentences [Sorensen] |
9129 | I can buy any litre of water, but not every litre of water [Sorensen] |
651 | Eurytus showed that numbers underlie things by making pictures of creatures out of pebbles [Eurytus, by Aristotle] |
9122 | God cannot experience unwanted pain, so God cannot understand human beings [Sorensen] |