Ed Lake reviews Kluge by Gary Marcus and The Drunkard’s Walk by Leonard Mlodinow, in The Telegraph:
Why is our language so vague and ambiguous? Why are we so bad at sticking to plans, or keeping track of how we know what we know, or generally doing any of the things you’d hope to be able to do with a superlatively well-engineered brain?
Because it was a kluge. Evolution doesn’t, in fact, tend to perfection: it goes with what works and tinkers with it later. That’s why the retinas of vertebrates seem to be installed backwards, giving us all blind spots in the middle of our visual fields. Eyes like that do the job well enough, and there’s no way of flipping the retina while preserving decent vision across intermediate generations. So we’re stuck with them.
Likewise the mind: our meagre reasoning capacity is an afterthought, spatchcocked on to the ancestral systems that have the reins where practical decision-making is concerned. If only our higher mental functions could dominate; alas, the lizard- brain parts have seniority.