If these conclusions are correct, they have an important practical bearing. Struggle and effort are essential to progress. Not inborn talent alone, but the use which one makes of it, counts in evolution. The effects of use and disuse are cumulative. The hard-fought battle of past generations becomes an easy victory in the present, just because of the strength acquired and handed down from the past struggle. Persistent variation toward evil is in time weeded out by natural selection. And, while evil remains in the world, we are to lay up stores of strength for ourselves and our descendants by sturdily fighting it. But the effects of right living through a hundred generations are not overcome by the criminal life of one or two. Evil surroundings weigh more in producing criminals than heredity, and their children are not irreclaimable.
The struggles and victories of each one of us encourage the rest. There is, to borrow Mr. Huxley's language, not only a survival of the fittest, but a fitting of as many as possible to survive. And in the midst of the hardest struggle there is the peace which comes from the assurance of a glorious triumph.
Condensed Chart of Development of the Main Line of the Animal Kingdom leading to Man.
| | ORGANS | MOST RAPIDLY PHYLOGENETIC | | APPROACHING | ADVANCING SERIES. | NEW ATTAINMENTS. | CULMINATION. | ORGANS. -------------+----------------------------+---------------+-------------- Amoeba. | Cell. | | -------------+----------------------------+---------------+-------------- Volvox. | Somatic and reproductive | | Reproductive. | cells | | -------------+----------------------------+---------------+-------------- Hydra. | Simple reproductive organs.| | Reproductive. | Gastro vascular cavity. | | | (Tissues). | | -------------+----------------------------+---------------+-------------- Turbellaria. | D | Complex reproductive | Reproductive. | Digestive. | e | Organs. Supra-oes. | | | v | Ganglion and cords. | | | e | Sense organs. | | | l | Body wall.ns. | | | o | | | | p | | | -------------+---|------------------------+---------------+-------------- Annelid. | O | Perivisceral Cavity. | | | r | Intestine. Circulatory | | | g | system. Nephridia. | | | a | Visual eyes. | | | n | | | | s | | | -------------+---+------------------------+---------------+-------------- Primitive | Notochord. Fins. | | Vertebrate. | | | -------------+----------------------------+---------------+-------------- Fish. | Backbone (incomplete). | Digestive. | Muscles. | Paired Fins. Jaws from | | | Branchial Arches. Simple | | | heart. Air Bladder. Brain. | | -------------+----------------------------+---------------+-------------- Amphibian. | Legs. Lungs. Cerebrum | | Muscles. | increases from this | | | form on. | | -------------+----------------------------+---------------+-------------- Reptile. | Double heart. | | Muscles and | | | appendages. -------------+----------------------------+---------------+-------------- Lower | Constant high temperature | | Muscles and Placental | Placenta. | Muscle. | appendages. Mammals. | | | -------------+----------------------------+ +-------------- Ape. | Erect posture. Hand. Large | | Brain. | cerebrum. | | | | | | | | -------------+----------------------------+---------------+-------------- Man. | Very large cerebrum. | | BRAIN. | Personality. | | | | | | | | -------------+----------------------------+---------------+--------------