34 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] |
6007 | If you know your father, but don't recognise your father veiled, you know and don't know the same person [Eubulides, by Dancy,R] |
6006 | If you say truly that you are lying, you are lying [Eubulides, by Dancy,R] |
6008 | Removing one grain doesn't destroy a heap, so a heap can't be destroyed [Eubulides, by Dancy,R] |
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] |
6685 | 'Subjectivism' is an extension of relativism from the social group to the individual [Graham] |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
6699 | The chain of consequences may not be the same as the chain of responsibility [Graham] |
6698 | Negative consequences are very hard (and possibly impossible) to assess [Graham] |
6700 | We can't criticise people because of unforeseeable consequences [Graham] |
6704 | Egoism submits to desires, but cannot help form them [Graham] |
6701 | Rescue operations need spontaneous benevolence, not careful thought [Graham] |
6693 | 'What if everybody did that?' rather misses the point as an objection to cheating [Graham] |
6691 | It is more plausible to say people can choose between values, than that they can create them [Graham] |
6688 | Life is only absurd if you expected an explanation and none turns up [Graham] |
6705 | Existentialism may transcend our nature, unlike eudaimonism [Graham] |
6690 | A standard problem for existentialism is the 'sincere Nazi' [Graham] |
6689 | The key to existentialism: the way you make choices is more important than what you choose [Graham] |
6706 | The great religions are much more concerned with the religious life than with ethics [Graham] |
6709 | Western religion saves us from death; Eastern religion saves us from immortality [Graham] |