23 ideas
8074 | There is a five shilling fine for each point of divergence from the thinking of Aristotle [Oxford Univ 1350] |
18781 | Inconsistency doesn't prevent us reasoning about some system [Mares] |
18789 | Intuitionist logic looks best as natural deduction [Mares] |
18790 | Intuitionism as natural deduction has no rule for negation [Mares] |
18787 | Three-valued logic is useful for a theory of presupposition [Mares] |
18793 | Material implication (and classical logic) considers nothing but truth values for implications [Mares] |
18784 | In classical logic the connectives can be related elegantly, as in De Morgan's laws [Mares] |
18786 | Excluded middle standardly implies bivalence; attacks use non-contradiction, De M 3, or double negation [Mares] |
18780 | Standard disjunction and negation force us to accept the principle of bivalence [Mares] |
18782 | The connectives are studied either through model theory or through proof theory [Mares] |
18783 | Many-valued logics lack a natural deduction system [Mares] |
18792 | Situation semantics for logics: not possible worlds, but information in situations [Mares] |
18785 | Consistency is semantic, but non-contradiction is syntactic [Mares] |
18788 | For intuitionists there are not numbers and sets, but processes of counting and collecting [Mares] |
18791 | In 'situation semantics' our main concepts are abstracted from situations [Mares] |
4061 | The right to life is not a right not to be killed, but not to be killed unjustly [Thomson] |
4057 | A newly fertilized ovum is no more a person than an acorn is an oak tree [Thomson] |
4695 | Maybe abortion can be justified despite the foetus having full human rights [Thomson, by Foot] |
4059 | It can't be murder for a mother to perform an abortion on herself to save her own life [Thomson] |
4696 | The foetus is safe in the womb, so abortion initiates its death, with the mother as the agent. [Foot on Thomson] |
4058 | Is someone's right to life diminished if they were conceived by a rape? [Thomson] |
4060 | The right to life does not bestow the right to use someone else's body to support that life [Thomson] |
4062 | No one is morally required to make huge sacrifices to keep someone else alive for nine months [Thomson] |