As C. L. Redfield has secured considerable publicity for his attempt to bolster up the Lamarckian theory, it deserves a few words of comment. His contention is that "the energy in animals, known as intelligence and physical strength, is identical with the energy known in mechanics, and is governed by the same laws." He therefore concludes that (1) an animal stores up energy in its body, in some undescribed and mystical way, and (2) that in some equally undescribed and mystical way it transmits this stored-up energy to its offspring. It follows that he thinks superior offspring are produced by parents of advanced age, because the latter have had more time to do work and store up energy for transmission. In his own words:

The question of the influence of parental age on the characters of the offspring is one of great importance, for the solution of which the necessary facts have not yet been gathered together. The data compiled by Mr. Redfield are of value, but his interpretation of them can not be accepted for the following reasons.

1. In the light of modern psychology, it is absurd to lump all sorts of mental ability under one head, and to suppose that the father's exercise of reasoning power, for example, will store up "energy" to be manifested in the offspring in the shape of executive or artistic ability. Mental abilities are much subdivided and are inherited separately. Mr. Redfield's idea of the process is much too crude.

Moreover, Mr. Redfield's whole conception of the increase of intelligence with increase of age in a parent shows a disregard of the facts of psychology. As E. A. Doll has pointed out,[196] in criticising Mr. Redfield's recent and extreme claim that feeble-mindedness is the product of early marriage, it is incorrect to speak of 20-, 30-, or 40-year standards of intelligence; for recent researches in measurement of mental development indicate that the heritable standard of intelligence of adults increases very little beyond the age of approximately 16 years. A person 40 years old has an additional experience of a quarter of a century, and so has a larger mental content, but his intelligence is still nearly at the 16-year level. Mental activity is the effect, not the cause, of mental growth or development. Education merely turns inherent mental powers to good account; it makes very little change in those powers themselves. To suppose that a father can, by study, raise his innate level of intelligence and transmit it at the new level to his son, is a naÏve idea which finds no warrant in the known facts of mental development.

2. In his entire conception of the storing-up and transmission of energy, Mr. Redfield has fallen victim to a confusion of ideas due to the use of the same word to mean two different things. He thinks of energy as an engineer; he declares the body-cell is a storage battery; he believes that the athlete by performing work stores up energy in his body (in some mysterious and unascertainable way) just as the clock stores up energy when it is wound. The incorrectness of supposing that the so-called energy of a man is of that nature, is remarkable. If, hearing Bismarck called a man of iron, one should analyze his remains to find out how much more iron he contained than ordinary men, it would be a performance exactly comparable to Mr. Redfield's, when he thinks of a man's "energy" as something stored up by work.

As a fact, a man contains less energy, after the performance of work, than he did at the start. All of his "energy" comes from the metabolism of food that he has previously eaten. His potential energy is the food stored up in his body, particularly the glycogen in the liver and muscles.[197]

Why, then, can one man run faster than another? Mr. Redfield thinks it is because the sprinter has, by previous work, stored up energy in his body, which carries him over the course more rapidly than the sluggard who has not been subjected to systematic training. But the differences in men's ability are not due to the amount of energy they have stored up. It is due rather to differences in their structure (using this word in a very broad sense), which produce differences in the efficiency with which they can use the stored-up energy (i.e., food) in their bodies. A fat Shorthorn bull contains much more stored-up energy than does a race horse, but the latter has the better structure—coÖrdination of muscles with nervous system, in particular—and there is never any doubt about how a race between the two will end. The difference between the results achieved by a highly educated thinker and a low-grade moron are similarly differences in structural efficiency: the moron may eat much more, and thereby have more potential energy, than the scholar; but the machine, the brain, can not utilize it.

The effects of training are not to store up energy in the body, for it has been proved that work decreases rather than increases the amount of energy in the body. How is it, then, that training increases a man's efficiency? It is obviously by improving his "structure," and probably the most important part of this improvement is in bringing about better relations between the muscles and the nerves. To pursue the analogy which Mr. Redfield so often misuses, the effect of training on the human machine is merely to oil the bearings and straighten out bent parts, to make it a more efficient transformer of the energy that is supplied to it.

The foundation stone of Mr. Redfield's hypothesis is his idea that the animal by working stores up energy. This idea is the exact reverse of the truth. While the facts which Mr. Redfield has gathered deserve much study, his idea of "Dynamic Evolution" need not be taken seriously.[198]