| Purpose and available means | A purpose guides search; a new means can reveal a different worthwhile contribution. |
| Local plausibility and whole feasibility | Each initiative can look affordable while claiming the same scarce contribution. |
| Learning and commitment | Useful preparation can reduce uncertainty without warranting realization. |
| Coherence and plurality | Connected answers are needed for the choice, but independent purposes and branches need not become one project. |
| Continuity and reconsideration | A changed premise can defeat a commitment while leaving its earlier observations and unrelated work valid. |