The human mind is irrational. However, the subconscious is split up into three parts-the id, the superego, and the ego- to ensure society does not become full of crazy, impulsive beasts.. The id, defined by Freud, is the pleasure-seeking part of a mind that drives people to action; the ego and the superego, though, tell a person what they are legitimately capable of and whether the action is morally "right" or not, respectively. Because of this basic makeup of the human mind, Chet Raymo's essay "A Measure Of Restraint" falls on deaf years.

He claims that a "measure of restraint" needs to be shown because scientific discoveries and creations are potentially too dangerous. With references to cesium-137, to radium, and to a luminescent plant with animal genes, Raymo conveys his point clearly: without proper caution for scientific discoveries and experiments, the "instrument of healing" will become the "instrument of death". However, the same "fast buck" that motivated someone to sell radioactive cesium-137 will drive the scientists of today to continue to perform dangerous experiments. Even though these new tests and trials might be harmful and breach the given laws of nature, the superego of a scientist says "you're doing good for the community- for the world!" and the id of a scientist just laughs- because it has motivated a person to fulfill his selfish desires for fame, fortune, and domination of nature.