O'Neill was one of the most famous advocates of a way of writing called 'naturalism.' This involved both a technique and a way of viewing life. Essentially, the literary concept of naturalism grew out of the concept of realism during the nineteenth century. The realist had wanted to 'hold up a mirror to life' and render a very accurate picture of life. The naturalist wanted to go a step further and examine life as would a scientist. Thus the technique of the naturalist involves viewing life with scientific objectivity. For the naturalist, man is controlled by basic urges and can do very little to determine his own destiny. Forces of environment and biological instinct combine to control man's life. These basic and elemental urges place man in a position similar to that of animals. But O'Neill also accepted the psychological urges as a part of man's basic driving force. In his plays, O'Neill shows characters being driven by forces which they cannot understand or conquer. A man born in one type of environment is influenced accordingly, to a point where his basic actions in life are governed by these environmental forces. Carried to an extreme, this view leads to determinism, that is, the idea that man can do nothing for himself and is constantly at the mercy of forces outside himself. A typical image used by the naturalist is that of a person being trapped or being in a cage. In his earlier works, O'Neill often used the physical image of the cage (as in The Hairy Ape) to suggest the position of man caught or trapped in an alien and hostile universe. Which one of the following is most suitable for the title of the passage?