We live in a golden age of science writing, where weighty subjects such as quantum mechanics, genetics and cell theory are routinely rendered intelligible to mass audiences. Nonetheless, it remains rare for even the most talented science writers to fuse their work with a deep knowledge of the arts.

One such rarity is the Italian theoretical physicist Carlo Rovelli who, like some intellectual throwback to antiquity, treats the sciences and the humanities as complementary areas of knowledge and is a subtle interpreter of both. His best-known work is Seven Brief Lessons on Physics, which was a bestseller, most notably in Italy, where he is also well known for his erudite articles in newspapers such as Corriere della Sera.

He writes on subjects as varied as classical philosophy, the meaning of science, the role of religion, the nature of black holes and the sociopolitical revelation of reading Hitler’s Mein Kampf (fascism grows from fear, not strength). His new book is a collection of his newspaper articles, a series of finely wrought essays that draw on an impressive hinterland of cultural and scientific learning.

There is, for example, a fascinating exploration of Dante’s understanding of the shape of the cosmos, which, says Rovelli, anticipated Einstein’s brilliant intuition of a “three sphere” universe by six centuries. And a rather moving meditation on the nature of an octopus’s consciousness that could make even the most devoted pescatarian hesitate before ordering a dish made from our shockingly underrated eight-limbed friends.

Rovelli asks what it must feel like to be an octopus with a brain that is spread throughout its body and with arms that can think independently. And he wonders that if evolution could come up with such a radically different form of intelligence on this tiny planet, then what more complex entities might inhabit other parts of the universe? If nothing else, an encounter with a life form with such a different sensory and information processing system, he says, should help clarify “what is essential and what is an accessory to what we call consciousness”.

The essay format makes for an entertaining and enlightening journey through a wide field of disciplines, which, thanks to Rovelli’s authoritative voice and clarity of thought, never seems random or disjointed.

What also holds the pieces together is Rovelli’s perspective as a classic European liberal leftist humanist. It’s an attractive political sensibility, particularly in these strange days, and provides a welcome moral framework to much of the writing. But sometimes it lapses into eloquent or even just plain platitude, particularly when the author states his beliefs in bald terms: collaboration is better than conflict, social inequality is bad and war should be avoided.

Set against his almost effortless appreciation of ideas, this stripe of prefabricated idealism can seem politically simplistic. It’s a tendency that becomes apparent in an essay about an archaeological find four years ago at Nataruk in Kenya, where the remains of 27 people were unearthed who were killed in a massacre dating back ten millennia.

A common theory in anthropology is that violence is not intrinsic to human nature but, rather, grew out of the agricultural revolution. But as the Nataruk find predates agriculture in the area, it would suggest that warfare is more deep seated than current anthropological thinking would have us believe.

Does that mean, as Rovelli puts it, that we are more akin to our close relatives and prolific warriors, the chimpanzees, or to our other relatives and promiscuous lovers, the bonobos? Well, he says, Nataruk could still prove that violence is a recent arrival in the human story, triggered not by agriculture but a less nomadic lifestyle in which land defence became more important.

“The disgust for war that many of us feel may be rooted in the instinctual mental fabric of our species,” he writes.

It may indeed, but it’s also possible that warfare has played its counterintuitive part in the extraordinary proliferation of humanity. That’s an unpalatable thought in almost every way, but the truth is there are many places in history where kindness has been less important than progress.

• There Are Places in the World Where Rules Are Less Important Than Kindness by Carlo Rovelli is published by Penguin (£20). To order a copy go to guardianbookshop.com. Delivery charges may apply