12 ideas
| 3653 | My Meditations are the complete foundation of my physics [Descartes] |
| 14782 | Philosophy is an experimental science, resting on common experience [Peirce] |
| 14787 | Self-contradiction doesn't reveal impossibility; it is inductive impossibility which reveals self-contradiction [Peirce] |
| 4736 | Truth is such a transcendentally clear notion that it cannot be further defined [Descartes] |
| 14783 | Logic, unlike mathematics, is not hypothetical; it asserts categorical ends from hypothetical means [Peirce] |
| 14788 | Mathematics is close to logic, but is even more abstract [Peirce] |
| 14786 | Some logical possibility concerns single propositions, but there is also compatibility between propositions [Peirce] |
| 14789 | Experience is indeed our only source of knowledge, provided we include inner experience [Peirce] |
| 14785 | The world is one of experience, but experiences are always located among our ideas [Peirce] |
| 19087 | The meaning or purport of a symbol is all the rational conduct it would lead to [Peirce] |
| 14784 | Ethics is the science of aims [Peirce] |
| 3652 | I can't prove the soul is indestructible, only that it is separate from the mortal body [Descartes] |