Nor must we overlook the fact that as evolution progresses, not only do the factors increase in complexity, but also the relations among them. Originally, _a_ is directly and simply connected with _b_, while _c_ is directly and simply connected with _d_. But eventually, the connections between _a_ and _b_, and between _c_ and _d_, become very indirect and involved. On the one hand, as the first illustration shows us, sapidity and nutritiveness are closely bound together; as are also the stimulation caused by the one and the contraction which utilizes the other. But, as we see in the last illustration, the connection between the visible traits of an estate and those characters which constitute its value, is at once remote and complicated; while the transition from the purchaser's highly composite motive to the numerous actions of sensory and motor organs, severally intricate, which effect the purchase, is through an entangled plexus of thoughts and feelings constituting his decision. After this explanation will be apprehended a truth otherwise set forth in the _Principles of Psychology_. Mind consists of feelings and the relations among feelings. By composition of the relations, and ideas of relations, intelligence arises. By composition of the feelings, and ideas of feelings, emotion arises. And, other things equal, the evolution of either is great in proportion as the composition is great. One of the necessary implications is that cognition becomes higher in proportion as it is remoter from reflex action; while emotion becomes higher in proportion as it is remoter from sensation. And now of the various corollaries from this broad view of psychological evolution, let us observe those which concern the motives and actions that are classed as moral and immoral.