28 ideas
| 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] |
| 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] |
| 7621 | Special relativity, unlike general relativity, was operationalist in spirit [Putnam on Einstein] |
| 5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
| 22955 | Einstein took causation to be the bedrock of physics [Einstein, by Coveney/Highfield] |
| 20638 | General relativity assumes laws of nature are the same in all frames of reference [Einstein, by Close] |
| 20636 | Newton is a special case of Einstein's general theory, with an infinite speed of light [Einstein, by Close] |
| 21230 | The theory is 'special' because it sticks to observers moving straight, at constant speeds [Einstein, by Farmelo] |
| 21231 | Assume the speed of light is constant for all observers, and the laws of physics are the same [Einstein, by Farmelo] |
| 20634 | General Relativity says there is no absolute force or acceleration [Einstein, by Close] |
| 20648 | Mass is a measure of energy content [Einstein] |
| 21232 | Space-time arises from the connection between measurements of space and of time [Einstein, by Farmelo] |
| 1558 | Clearly the gods ignore human affairs, or they would have given us justice [Thrasymachus] |
| 7626 | I do not believe in a personal God [Einstein] |