| Ross distinguishes between derived and underived prima facie duties. |
| New forms of dead matter may be derived, but new living forms are underived. |
| The mind, through its original and underived thinking, is itself the pattern of such a synthesis. |
| Causal theories of mental content presuppose that mental contents are underived, hence attempt to explain how underived meaning arises. |
| So derived reasons are variable, and underived ones invariant. |
| The question is how exactly the constructivist idea of the underived authority of reason escapes the original problem of circularity. |
