6. We see then that the powers which control life are three, of which the first by its heat produces general warmth, the second by its moisture keeps damp that which is warmed, so that the living being is kept in an intermediate condition by the equal balance of the forces exerted by the quality of each of the opposing natures (the moist element not being dried up by excess of heat, nor the hot element quenched by the prevalence of moisture); and the third power by its own agency holds together the separate members in a certain agreement and harmony, connecting them by the ties which it itself furnishes, and sending into them all that self-moving and determining force, on the failure of which the member becomes relaxed and deadened, being left destitute of the determining spirit.