A Review of “Kluge: The Haphazard Evolution of the Human Mind”

Gary Marcus's book, Kluge: The Haphazard Evolution of the Human Mind, is a body blow to religious belief. It performs a double service to us by showing how the evolution of our brain accounts for why we think so poorly, and in so doing goes a long way toward showing that religious belief is a product of this poor thinking. Very highly recommended.

Gary Marcus, professor of psychology at New York University, begins chapter one by saying: “If mankind were the product of some intelligent, compassionate designer, our thoughts would be rational, our logic impeccable. Our memory would be robust, our recollections reliable.” (p. 1). Instead, our brains evolved as a kluge. A kluge “is a clumsy or inelegant—yet surprisingly effective solution—to a problem.” Just picture a house constructed in stages by different contractors at later times and you can get the picture. The original bathroom might be extended, which in turn takes away some space from the living room, or an added bedroom which does away with the bathroom upstairs. Without starting all over with a completely new floor plan, we get a kludge

We see this in the human spine, “which is a lousy solution to supporting the load in an upright, two-legged creature. It would have made a lot more sense to distribute our weight across four cross-braced columns. Instead, all our weight is borne by a single column, putting enormous stress on the spine.” But we are stuck with it because "the spine evolved from that of four legged creatures, and standing up poorly is better than not standing at all.” (p. 5) The same goes for the retina, the tubing that runs from the testis to the urethra and so on. Our body is a kluge, as is our brain. Evolution cannot start over. All it can do is select the next best thing that’s available, and it works. But it’s not the same as starting over. That’s his argument. And it affects how we think since this is how our brains evolved. It didn’t get a chance to start all over. It cannot go back and do that. It can only evolve on top of our more primitive reptilian brains. “Natural selection therefore tends to favor genes that have immediate advantages, discarding other options that might function better in the long term.” (p.12). “The end product tends to be a kluge.” (p. 14).

Because we have three brains built on top of one another, the hindbrain (or repillian brain), the midbrain (the Limbic System) and the forebrain (the Neocortex) it affects our memories, beliefs, choices, language, and pleasure.

Memory is the “mother of all kluges,” Marcus argues in chapter two. It is prone to distortion, conflation and failure. “Human memory is in many ways a recalcitrant mess.” (p. 20) We would do well with a “postal code memory,” like how a computer accesses a specific address for each bit of information. Instead, because of the way the brain was formed in stages, we have a contextual memory. We “pull things out of our memory by using context, or clues, that hints at what we are looking for.” (p. 21) This type of memory is found in apes, rats, and even spiders and snails. We are more apt “to remember what we know about gardening when we are in the garden,” and we’re more apt “to remember what we know about cooking when we’re in the kitchen.” (p. 21) This helped the lower animals survive in much the same way as agency detection did for them (by seeing faces of predators in the leaves and sounds in the forest). But just as agency detection created many false alarms, so also there is a price to pay for contextual memory. The price of this type of memory is reliability. The reason why we can’t remember what we had for breakfast yesterday is that “yesterday’s breakfast is too easily confused with that of the day before, and the day before that.” (p. 23). “Whenever context changes, there’s a problem.” And so our memories can blur together, and as they do, they are continually revised, even leading to distortion and false memories. “To build a truly reliable memory, fit for the requirement of human deliberative reasoning, evolution would have had to start over. And despite its power and elegance, that’s the one thing evolution just can’t do.” (p. 39).

When it comes to our beliefs, Marcus argues in chapter three, we are not objective machines even though most people think they have arrived at the truth logically with a capital ”T”. Instead, “our capacity for belief is haphazard, scarred by evolution and contaminated by emotions, moods, desires, goals, and simple self-interest.” (p. 41). “Because evolution built belief mainly out of off-the-shelf components that evolved for other purposes, we often lose track of where our beliefs come from—if we ever knew—and even worse, we are often completely unaware of how much we are influenced by irrelevant information.” (p. 42) “We feel as if our beliefs are based on cold, hard facts, but often they are shaped by our ancestral system in subtle ways that we are not even aware of.” (p. 53). Marcus proceeds to inform us of the various ways we gain and maintain our beliefs, many illogical. We believe what is familiar. We seek to confirm it. We will cling to what we believe despite evidence to the contrary. We fail to consider disconfirming evidence. “Once we decide something is true (for whatever reason), we often make up reasons for believing it.” We scrutinize ideas more carefully if we don’t like them than if we are familiar with them. This is because evolved creatures “were often forced to act rather than think.” (p. 68).

Of course this all affects our choices, chapter four. Our choices rarely are based on the future but on the immediate problem before us, just like the lower animals from whom we evolved. Marcus quotes a line from his father. “all choices are emotional.” (p.87). What he means is that “when context tells us one thing, but rationality another, rationality often loses.” (p.84)

In chapter five Marcus shows us that the language we use is less than perfect. “To be perfect, a language would presumably have to be unambiguous, systematic, stable, nonredundant, and capable of expressing any and all of our thoughts.” (p. 97). But this doesn’t describe any known language because language evolved with our brains.

In chapter six Marcus discusses pleasure as “the ideal adaptation” (p. 125), and as such “the pleasure system as a whole is a kluge, from top to bottom.” (p. 127). “In short, we do everything in our power to make ourselves happy and comfortable with the world, but we stand perfectly ready to lie to ourselves if the truth doesn’t cooperate.” (p. 142)

In chapter seven Marcus tells more about us, “when things fall apart.” We are prone to distraction, procrastination, and we chicken out. One quarter of us at any given moment “suffers from one clinical disorder or another.” (p. 149). He concludes: “…it seems safe to say that no intelligent and compassionate designer would have built the human mind to be quite as vulnerable as it is.” (p. 160). Right that!

In his concluding chapter Marcus provides us with some strategies for dealing with the kludge of our brains, which are nothing short of critical thinking skills:

1) Whenever possible, consider alternative hypotheses; 2) Reframe the question; 3) Always remember that correlation does not entail causation; 4) Never forget the size of your sample; 5) Anticipate your own impulsivity and pre-commit[ment]; 6) Don’t just set goals. Make contingency plans; 7) Whenever possible, don’t make important decisions when you are tired or have other things on your mind; 8) Always weigh benefits against costs; 9) Imagine that your decisions may be spot-checked; 10) Distance yourself; 11) Beware the vivid, the personal, and the anecdotal; 12) Pick your spots; and 13) Try to be rational.

His closing warning: “..the truth is that without special training, our species is inherently gullible.” (p. 174)

When it comes to religious beliefs a believer should especially pay close attention to 1,3,5,10,11,and 13. This is the whole reason why I think they should take the Outsider Test for Faith.