5 ideas
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] |
18431 | Internal relations combine some tropes into a nucleus, which bears the non-essential tropes [Simons, by Edwards] |
20523 | Property is theft! [Proudhon] |