12 ideas
| 291 | Don't assume that wisdom is the automatic consequence of old age [Plato] |
| 13338 | '"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski] |
| 13337 | A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules [Tarski] |
| 13335 | Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski] |
| 13336 | A language containing its own semantics is inconsistent - but we can use a second language [Tarski] |
| 13339 | A sentence is satisfied when we can assert the sentence when the variables are assigned [Tarski] |
| 13340 | Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski] |
| 13341 | Using the definition of truth, we can prove theories consistent within sound logics [Tarski] |
| 4304 | Descartes says there are two substance, Spinoza one, and Leibniz infinitely many [Cottingham] |
| 4303 | The notion of substance lies at the heart of rationalist metaphysics [Cottingham] |
| 293 | Being unafraid (perhaps through ignorance) and being brave are two different things [Plato] |
| 4306 | For rationalists, it is necessary that effects be deducible from their causes [Cottingham] |