[Mr. Steinbeck's] virtuosity in a purely technical way has tended to obscure his themes. He has published eight volumes of fiction, which represent a variety of forms and which have thereby produced an illusion of having been written from a variety of points of view…. [Attention] has been diverted from the content of Mr. Steinbeck's work by the fact that when his curtain goes up, he always puts on a different kind of show.

Yet there is in Mr. Steinbeck's fiction a substratum which remains constant and which gives it a certain weight. What is constant in Mr. Steinbeck is his preoccupation with biology. He is a biologist in the literal sense that he interests himself in biological research. The biological laboratory in the short story called The Snake is obviously something which he knows at first hand and for which he has a strong special feeling; and it is one of the peculiarities of his vocabulary that it runs to biological terms. But the laboratory described in The Snake, the tight little building above the water, where the scientist feeds white rats to rattlesnakes and fertilizes starfish ova, is also one of the key images of his fiction. It is the symbol of Mr. Steinbeck's tendency to present human life in animal terms.

Mr. Steinbeck almost always in his fiction is dealing either with the lower animals or with humans so rudimentary that they are almost on the animal level; and the relations between animals and people are as intimate as those in the zoöphile fiction of David Garnett and D. H. Lawrence…. Mr. Steinbeck does not give the effect, as Lawrence or Kipling does [however], of romantically raising the animals to the stature of human beings, but rather of assimilating the human beings to animals. (pp. 35-7)

And Steinbeck does not … dwell much, as Lawrence likes to do, on the perfections of his various beasts each after its own kind. It is the habits and behavior of the animals, not the impression they make, that interests him.

The chief subject of Mr. Steinbeck's fiction has been thus not those aspects of humanity in which it is most thoughtful, imaginative, constructive, nor even those aspects of animals that seem most attractive to humans, but rather the processes of life itself. In the ordinary course of nature, living organisms are continually being destroyed, and among the principal things that destroy them are the predatory appetite and the competitive instinct that are necessary for the very survival of eating and breeding creatures. This impulse of the killer has been preserved in a simpleton like Lennie of Of Mice and Men in a form in which it is almost innocent; and yet Lennie has learned from his more highly developed friend that to yield to it is to do something "bad." In his struggle against the instinct, he loses. Is Lennie bad or good? He is betrayed as, the author implies, all our human intentions are, by the uncertainties of our animal nature. And it is only, as a rule, on this primitive level that Mr. Steinbeck deals with moral questions: the virtues like the crimes, for him, are still a part of these plan less and almost aimless, of these almost unconscious, processes. The preacher in The Grapes of Wrath … evidently gives expression to Mr. Steinbeck's own point of view: "This here ol' man jus' lived a life an' jus' died out of it. I don't know whether he was good or bad, but that don't matter much. He was alive, an' that's what matters. An' now he's dead, an' that don't matter….

The subject of The Grapes of Wrath, which is supposed to deal with human society, is the same as the subject of The Red Pony, which is supposed to deal with horses: loyalty to life itself. The men who feel themselves responsible for having let the red pony die must make up for it by sacrificing the mare in order that a new pony may be brought into the world alive. And so Rose of Sharon Joad, with her undernourished baby born dead, must offer her milk … to another wretched victim of famine and flood, on the point of death from starvation. To what end should ponies and Oakies continue to live on the earth? "And I wouldn' pray for a ol' fella that's dead," the preacher goes on to say. "He's awright. He got a job to do, but it's all laid out for 'im an' there's on'y one way to do it. But us, we got a job to do, an' they's a thousan' ways, an' we don' know which one to take. An' if I was to pray, it'd be for the folks that don't know which way to turn." (pp. 38-9)

[What] differentiates Mr. Steinbeck's picture of a labor movement with radical leadership [in In Dubious Battle] from most treatments of such subjects of its period is again the biological point of view. The strike leaders, here, are Communists, as they are in many labor novels, but In Dubious Battle is not really based on the formulas of Communist ideology. The kind of character produced by the Communist movement and the Communist strategy in strikes (of the Communism of the day before yesterday) is described by Mr. Steinbeck, and it is described with a certain amount of admiration; yet the party member of In Dubious Battle does not talk like a Marxist of even the Stalinist revision. The cruelty of these revolutionists, though they are working for a noble ideal and must immolate themselves in the struggle, is not palliated by the author any more than the cruelty of the half-witted Lennie; and we are made to feel all through the book that, impressive though the characters may be, they are presented primarily as examples of how life in our age behaves. There is developed in the course of the story … a whole philosophy of "group-man" as an "animal." (pp. 39-40)

[The] old pioneer of The Leader of the People describes a westward migration which he himself once led as "a whole bunch of people made into one big crawling beast…. Every man wanted something for himself, but the big beast that was all of them wanted only westering."

This tendency on Steinbeck's part to animalize humanity is evidently one of the causes of his relative unsuccess at creating individual humans. The paisanos of Tortilla Flat are not really quite human beings: they are cunning little living dolls that amuse us as we might be amused by pet guinea-pigs, squirrels or rabbits. They are presented through a special convention which is calculated to keep them cut off from any kinship with the author or the reader. In The Grapes of Wrath, on the other hand, Mr. Steinbeck has summoned all his resources to make the reader feel his human relationship with the family of dispossessed farmers; yet the result of this, too, is not quite real. The characters of The Grapes of Wrath are animated and put through their paces rather than brought to life; they are like excellent character actors giving very conscientious performances in a fairly well-written play. Their dialect is well managed, but they always sound a little stagy; and, in spite of Mr. Steinbeck's efforts to make them figure as heroic human symbols, one cannot help feeling that these Okies, too, do not exist for him quite seriously as people. It is as if human sentiments and speeches had been assigned to a flock of lemmings on their way to throw themselves into the sea. One remembers the short story called Johnny Bear. Johnny Bear is another of Steinbeck's idiots: he has exactly the physique of a bear and seems in almost every way subhuman; but he is endowed with an uncanny gift for reproducing with perfect mimicry the conversations he overhears, though he understands nothing of their human meaning.

It is illuminating to look back from The Grapes of Wrath to one of the earliest of Steinbeck's novels, To a God Unknown. In this book he is dealing frankly with the destructive and reproductive forces as the cardinal principles of nature. In one passage, the hero is described by one of the other characters as never having "known a person": "You aren't aware of persons, Joseph; only people. You can't see units, Joseph, only the whole."… This story … evidently represents, on the part of Steinbeck just turned thirty, an honorably sincere attempt to find expression for his view of the world and his conception of the powers that move it. When you husk away the mawkish verbiage from the people of his later novels, you get down to a similar conception of a humanity not of "units" but lumped in a "whole," to a vision equally grim in its cycles of extinction and renewal.

Not, however, that John Steinbeck's picture of human beings as lemmings, as grass that is left to die, does not have its striking validity for the period in which we are living…. Many parts of the world are today being flooded with migrants like the Joads, deprived of the dignity of a human society, forbidden the dignity of human work, and made to flee from their houses like prairie-dogs driven before a prairie fire. (pp. 41-3)

The philosophy of Mr. Steinbeck is … not satisfactory in either its earlier or its later form. He has nothing to oppose to [the] vision of man's hating and destroying himself except an irreducible faith in life; and the very tracts he writes for the underdog let us see through to the biological realism which is his natural habit of mind. Yet I prefer his approach to the animal-man to the mysticism [for example] of Mr. Huxley; and I believe that we shall be more likely to find out something of value for the control and ennoblement of life by studying human behavior in this spirit than through the code of self-contemplation that seems to grow so rootlessly and palely in the decay of scientific tradition. (p. 44)

Mr. Steinbeck is equipped with resources of observation and invention which are exceptional and sometimes astonishing, and with color which is all his own but which does not, for some reason, possess what is called magic. It is hard to feel that any of his books, so far, is really first-rate. He has provided a panorama of California farm-life and California landscape which is unique in our literature; and there are passages in some ways so brilliant that we are troubled at being forced to recognize that there is something artistically bad about them…. [But we are often reminded] of the ever-present paradox of the mixture of seriousness and trashiness in the writing of Mr. Steinbeck. I am not sure that Tortilla Flat, by reason of the very limitations imposed by its folk tale convention, is not artistically his most successful work.

Yet there remains behind the journalism, the theatricalism and the tricks of his other books a mind which does seem first-rate in its unpanicky scrutiny of life. (pp. 44-5)