The conflicting demands of individual liberty, family loyalty and social solidarity (to name just three of many such principles) can’t be resolved by means of facts. There’s no one right formula.
Claiming otherwise isn’t a harmless error. It’s politically toxic. If Pinker believes that the facts are militating toward a scientific morality, what does that say about the people who take a different view of human flourishing? You no longer have a good-faith disagreement between people with different values — you have a clash between scientific enlightenment and intellectual backwardness. That’s not the basis for friendly interaction. It’s no accident that the more aggressive kinds of scientism — the so-called current New Atheism springs to mind — are bullying and intolerant. Intolerance isn’t conducive to human flourishing.
Indeed, and that’s why they scream stridently that anyone with a differing moral view or who dares to challenge scientific orthodoxies as “anti science.” The canard seeks to stifle debate rather than win it.