| 19597 | Logic (the theory of relations) should be applied to mathematics [Novalis] |
| 16863 | Does some mathematical reasoning (such as mathematical induction) not belong to logic? [Frege] |
| 16862 | The closest subject to logic is mathematics, which does little apart from drawing inferences [Frege] |
| 14462 | In modern times, logic has become mathematical, and mathematics has become logical [Russell] |
| 10035 | Mathematical Logic is a non-numerical branch of mathematics, and the supreme science [Gödel] |
| 11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
| 10985 | We should exclude second-order logic, precisely because it captures arithmetic [Read] |
| 13241 | The model theory of classical predicate logic is mathematics [Beall/Restall] |