A belief is an habitual connection of ideas. For example, to say that I believe prussic acid is a poison is to say that when the idea of drinking it occurs to me, the idea of it as a poison with all the other ideas which follow in the train of this will arise in my mind. Among these ideas, or objects present to me, is the sense of refusing to drink it. This, if I am in a normal condition, will be followed by an action of the nerves when needed which will remove the cup from my lips. It seems probable that every habitual connection of ideas may produce such an effect upon the will. If this is actually so, a belief and an habitual connection of ideas are one and the same.
In a mind which is capable of logical criticism of its beliefs, there must be a sensation of believing, which shall serve to show what ideas are connected. [—] The intellectual significance of beliefs lies wholly in the conclusions which may be drawn from them, and ultimately in their effects upon our conduct. For there does not seem to be any important distinction between two propositions which never can yield different practical results.