I believe that almost all important, useful ideas are simple. Peter Whittle has recently put it nicely in an autobiographical essay. "If a piece of work is heavy and complicated then it is wrong." . . . Some writers feel that to express their ideas in simple terms is degrading. Some use complexity to disguise the paucity of their material. In fact, simplicity is a virtue and when, as here, it is both original and useful, it can represent a real advance in knowledge.

Utility is the emotion pleading to be let into the house of pure reason and thereby enriching it.

I believe that almost all important, useful ideas are simple. Peter Whittle has recently put it nicely in an autobiographical essay. "If a piece of work is heavy and complicated then it is wrong." . . . Some writers feel that to express their ideas in simple terms is degrading. Some use complexity to disguise the paucity of their material. In fact, simplicity is a virtue and when, as here, it is both original and useful, it can represent a real advance in knowledge.

Consider the case of a person who holds a view with probability 1. Then coherence says that it is no use having a debate with them because nothing will change their mind.

Almost all thinking people agree that you should not have probability 1 (or 0) for any event, other than one demonstrable by logic, like 2 x 2 = 4.