The Commens Dictionary
Quote from ‘Letters to William James’
The Final Interpretant does not consist in the way in which any mind does act but in the way in which every mind would act. That is, it consists in a truth which might be expressed in a conditional proposition of this type: “If so and so were to happen to any mind this sign would determine that mind to such and such conduct.” By “conduct” I mean action under an intention of self-control. No event that occurs to any mind, no action of any mind can constitute the truth of that conditional proposition.