5 ideas
9560 | S5 provides the correct logic for necessity in the broadly logical sense [Fine,K] |
13831 | Logic is based on transitions between sentences [Prawitz] |
13825 | Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz] |
13823 | In natural deduction, inferences are atomic steps involving just one logical constant [Prawitz] |
467 | A virtue is a combination of intelligence, strength and luck [Ion] |