11 ideas
18812 | Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt] |
13344 | X follows from sentences K iff every model of K also models X [Tarski] |
13343 | A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski] |
13345 | Sentences are 'analytical' if every sequence of objects models them [Tarski] |
20180 | A happy and joyous life must largely be a quiet life [Russell] |
20177 | Boredom always involves not being fully occupied [Russell] |
20178 | Life is now more interesting, but boredom is more frightening [Russell] |
20176 | Boredom is an increasingly strong motivating power [Russell] |
20179 | Happiness involves enduring boredom, and the young should be taught this [Russell] |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |