Recall that when last we met our researcher from the Department of Alien Studies at the Alpha Centauri system's Interplanetary University, he was heading back to the dreary planet Earth - but armed, now, with an implanted translator that enables him to understand every word he hears or reads.
Long story short, what our researcher finds is that, when it comes to their values, a vast gulf lies between what humans say and what they do.
They are habitual hypocrites.
In practice, they constantly favor themselves over all others, their kin over unrelated folk, their near neighbours over far-away strangers, and so on. Yet, equally constantly, they preach doctrines of "universality," or "impartiality" - according to which one ought to care, and strive, just as much for the welfare of the far-away stranger as for one's own.
These doctrines show up, in embryonic form, in ancient religious tenets ("do unto others as you would have them do unto you") and are later refined, by philosophers, into supposed universal commands of reason &/or sentiment:
"...act only in accordance with that maxim through which you can at the same time will that it become a universal law."
"...actions are right in proportion as they tend to promote happiness; wrong as they tend to produce the reverse of happiness."
Later still, they inspire powerful political movements, demanding that people take at least as much care for others as for themselves, their families, and their friends.
Gradually, identification with such movements becomes a highly prized marker of intellectual & social superiority.
Behold the liberal left.
In due course, this interesting tendency achieves full flower in long & loud celebration of, & even abasement before, "the other," as such - and the more "other" the better.
Behold the radical left.
Our hapless researcher is thoroughly flummoxed. Could the great Selrahc Niwrad, Father of Centaurian Biology, have been wrong?
How could beings shaped by evolution have come up with & celebrated a set of values so thoroughly & systematically opposed, not only to their own usual behavior, but also, seemingly, to the promotion of their "inclusive fitness"?
Or, to repeat: "how can that be? What's to be made of it?"
What's wrong with these people?