In reflecting on the US 'electoral map', with the dominant patterns of belief in areas likely to vote Democrat compared by him with those that vote Republican, Steven Pinker discusses the clustering of ideological beliefs. Right-wing and left-wing belief systems, he says, rest on different conceptions of human nature, respectively tragic and utopian: the former emphasizing authority as a barrier against aggression and the 'danger of backsliding into barbarism'; the latter conceiving projects for a better society, the possibility of which is thought to be due to 'the malleability of human nature'. And with this broad difference of conception Pinker also aligns other differences of political belief.
While I do recognize the two large stereotypes with which he is playing here, I'm bound to say that if the American, or indeed any other, electorate really did break down in the way he says it does, humankind would be in even deeper trouble than it is. The belief that our species has characteristics and impulses that need restraining is not a monopoly of the right; it certainly shouldn't be. I'll make only passing reference here to the horrors of the last century, and then simply say that those today who believe that a reasonably peaceable society capable of fulfilling the needs and aspirations of its citizens is possible without the rule of law, and the necessary political force to back that law, are sadly deluded. 'Utopianism' in this domain should be about ensuring that authority is democratic and responsible, as opposed to tyrannical and arbitrary; and belief in the malleability of human nature should be limited to trying, so far as possible, to encourage its best rather than its worst features. But left-wing doesn't have to mean closing one's eyes to the more worrying realities of history, though unfortunately it sometimes has meant that.