A Difference of Degree?

8829126424_352fd6a30d_oAt the beginning of The Descent of Man, Charles Darwin argues that the differences in the mental faculties among all animals (including humans) are differences in degree rather than differences in kind.1 That is, there is a great deal of variation in the mental capabilities in the animal kingdom, but nothing about the mental capabilities of humans distinguishes them fundamentally from the rest of the animal kingdom. Darwin writes:

We have seen … that man bears in his bodily structure clear traces of his descent from some lower form; but it may be urged that, as man differs so greatly in his mental power from all other animals, there must be some error in this conclusion. . . . My object in this chapter is to shew (sic) that there is no fundamental difference between man and the higher mammals in their mental faculties.2

This claim is supposed to support Darwin’s overall view that natural selection accounts for the upward development of living things over time. Among the arguments Darwin puts forth in the third chapter of The Descent of Man are the following: 1. Mankind has the same senses as lower animals. 2. Mankind has some of the same instincts that lower animals possess (e.g., self-preservation, sexual love, terror, the love of the mother for her new-born offspring, affection for other friendly beings, etc.). 3. Mankind feels pleasure and pain, as lower animals do. 4. Mankind enjoys play, as lower animals do. 5. Mankind imitates other beings, as lower animals do. 6. Mankind has dreams, as lower animals do. 7. Mankind has mental individuality, as lower animals do. 8. Mankind uses language, as lower animals do. 9. Mankind appreciates beauty, as lower animals do. Darwin provides what he believes to be examples of each of these similarities between mankind and the rest of the animal kingdom.

In Mortimer J. Adler’s book, How to Think About the Great Ideas, we find an intriguing response to these claims of Darwin’s.3 Specifically, Adler argues for the following four claims to make the case that mankind is rational, and thus fundamentally different from the other animals:

  1. Only Humans Make Artistically. While other animals make beautiful things (e.g., an intricate spider web), they make them only by instinct. Humans make things by art. With animals, the production is always exactly the same, whereas with man, the production varies widely depending on the artist, his place in history, and his culture. It is true that animals use tools, but only mankind makes machine tools, or tools that produce further objects with little or no direct intervention of the machine’s maker (e.g., a printer or a soda bottling machine).
  2. Only Humans Think Discursively, or in Abstract Words. Other animals are able to solve some problems, but all of those problems arise from basic biological needs. Mankind solves problems that are unconnected to biological survival, such as “the problems of mathematics, the problems of philosophy, the problems of any of the theoretical or speculative sciences. . . . Only men sit down to think about what is important and not urgent.”4
  3. Only Humans Associate Politically. While other animals associate with one another socially, they do so only by instinct and in the same way from generation to generation. Only man devises new constitutions and laws that are influenced by aims higher than biological survival.
  4. Only Humans Have a History. While animals pass on a strictly biological inheritance, humans inherit culturally. Man has biological drives just as the beasts do, but by developing a culture based on what works and doesn’t work, man is able to rise above a beastly existence.

An honest comparison between the capabilities of animals and those of humans indicates that we humans were designed for a purpose higher than that of animals. When we turn to Bible, we find out precisely what that purpose is: “Fear God, and keep his commandments: for this is the whole duty of man” (Ecclesiastes 12:13). In Adler’s words:

Why, I keep asking myself and I’m asking you too, are there so many closed minds on this subject? I think partly the reason is that science is taught dogmatically in our schools. But I think there is another reason in part and that is the fact that evolution is one of the things which has emancipated man from religion, from the belief that God created man in His own image with a special dignity and a special destiny, including divine rewards and punishments. Let me repeat that: including divine rewards and punishments.5


  1. Great Books of the Western World, ed. Robert Hutchins (Chicago: Encyclopaedia Brittanica, 1952), 49:266ff. 

  2. ibid., 287. 

  3. (Peru: Carus, 2000), 78ff. 

  4. Ibid., 83, emp. added. 

  5. Ibid., 93-94. 

- 2017