27 ideas
22519 | Philosophers are revealed by their fears [Billington] |
5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
5737 | Predicate logic has connectives, quantifiers, variables, predicates, equality, names and brackets [Melia] |
5744 | First-order predicate calculus is extensional logic, but quantified modal logic is intensional (hence dubious) [Melia] |
5740 | Second-order logic needs second-order variables and quantification into predicate position [Melia] |
5741 | If every model that makes premises true also makes conclusion true, the argument is valid [Melia] |
21110 | An understanding of the most basic physics should explain all of the subject's mysteries [Krauss] |
21105 | In 1676 it was discovered that water is teeming with life [Krauss] |
5736 | No sort of plain language or levels of logic can express modal facts properly [Melia] |
5735 | Maybe names and predicates can capture any fact [Melia] |
5746 | The Identity of Indiscernibles is contentious for qualities, and trivial for non-qualities [Melia] |
5738 | We may be sure that P is necessary, but is it necessarily necessary? [Melia] |
5732 | 'De re' modality is about things themselves, 'de dicto' modality is about propositions [Melia] |
5739 | Sometimes we want to specify in what ways a thing is possible [Melia] |
5734 | Possible worlds make it possible to define necessity and counterfactuals without new primitives [Melia] |
5742 | In possible worlds semantics the modal operators are treated as quantifiers [Melia] |
5743 | If possible worlds semantics is not realist about possible worlds, logic becomes merely formal [Melia] |
5749 | Possible worlds could be real as mathematics, propositions, properties, or like books [Melia] |
5751 | The truth of propositions at possible worlds are implied by the world, just as in books [Melia] |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
21109 | Space itself can expand (and separate its contents) at faster than light speeds [Krauss] |
21104 | General Relativity: the density of energy and matter determines curvature and gravity [Krauss] |
21107 | Uncertainty says that energy can be very high over very short time periods [Krauss] |
21106 | Most of the mass of a proton is the energy in virtual particles (rather than the quarks) [Krauss] |
21112 | Empty space contains a continual flux of brief virtual particles [Krauss] |
21108 | The universe is precisely 13.72 billion years old [Krauss] |
21111 | It seems likely that cosmic inflation is eternal, and this would make a multiverse inevitable [Krauss] |