Australian philosopher Peter Singer, main exponent of a transhumanist ethics with books such as Animal Liberation and Practical Ethics, gets it right in his recent article Is Marx still relevant? (coinciding with 200th birthday anniversary of German thinker): The biggest mistake of marxism was a false view of human nature, blaming capitalist system for our vices and believing that some day, with socialism and the advent of a communist society with no classes, a new man free from greed, selfishness, lust for power, and desire of ostentation would be born. Because the fabric men and women are made of is the same, whether under slavery, feudalism, capitalism, or socialism. And communist utopia is as much absurd as unreachable.
In denying human nature we will bump again and again into reality and end up frustrated, seeing that scourges such as sexist violence, organized crime, bullying, or child abuse will never be eradicated. Of course, we have come a long way in this regard, specially in most developed countries, but only with the most childish naivety or out of ignorance about how we really are (partly by estimating that science is not applicable to the study of human behavior) we can come to believe that one day there will be no abuse, rape, murder (sexist or not) or any other barbaric act. And no need of police or prisons, as in leftists’ dreams.
Let us agree once and for all that there will always be psychopaths, sadistic, and evil people among us. And also, fortunately, good and compassionate ones. We are cooperative, but also predators. It’s human variability, for the best and the worst! No matter how good education and laws we lay on the grill, the worst of our nature will never be deleted; if anything, it can be minimized, as in most civilized societies (that’s why I’m afraid that in Spain the number of women murdered by their partners will never be lower than 40 or 50; in places such as Africa, Latin America, India, and the Islamic world, where the situation is much worse, there is a considerably wider margin of improvement).
Not even social engineering can alter the stuff we have been made of by evolution. As long as we remain Sapiens, our motives, impulses, fears, and desires will be the same (taking into account, of course, variability in behaviour). During Cold War, East Germans were not essentially different to West Germans. And nowadays Russians are not substantially different from those of 1960 or 1915. The human movie is always the same, with only minor adaptations in the script, despite cultural changes. Although, as Steven Pinker insists on remarking, humanity has never been better off: there is an undeniable progress, attributable to the strengthening of democracy (lately threatened by a national-populist wave), the growing interdependence between countries and the spread of education and cosmopolitanism.