(2.) _The so-called strength of a motive is the comparative prevalence which the will assigns to it by its own action._ It is impossible to erect any standard by which the intrinsic "strength" of motives can be determined previous to volition. "A cold intellection is not intrinsically commensurable with a deep emotion, nor a sentiment of taste with a feeling of obligation, nor a physical appetite with a sense of honor." Now by what standard can the comparative force of these influences be determined? There is no more commensurability between them than between "the brightness of day and the force of magnetic attractions." Or if we could possibly determine, by some rational _à priori_ method, that a feeling of obligation is intrinsically stronger than a physical appetite, or that the love of life is stronger _per se_ than a sense of duty, we can not affirm that the one or the other shall therefore uniformly and necessarily prevail. These influences derive all their prevalency, and consequently their comparative strength of motive, _from the will alone_. The will places its interest in the one or the other. It decides the mental position. "It settles the question of preferences between alternatives, dismisses the counter-motive from view, and closes the debate."[544] The "strength" of a motive, in its relation to the will, can only be known by the test of _prevalency_. This is unwittingly conceded by the necessitarian. He says "the strongest motive prevails because that is the strongest which the will chooses." This really concedes the position assumed by Dr. Whedon, that "the strength of a motive is the comparative prevalence which the will, in its own action, assigns to it, or the nearness to which the will comes to acting on account of it." Men do not always choose that which is most _desirable_, nor that which is most _eligible_, nor that which appears most _obligatory_. But from whatever motive men may choose to act, however base and unworthy, the necessitarian affirms it was intrinsically the strongest motive _because_ it was chosen; which simply amounts to this--the strongest motive is always chosen because the motive chosen is always the strongest motive.