The World Until Yesterday starts with a simple premise: traditional societies are actually far more representative of human experience than the now-dominant Western states. As relatively recent inventions, Western norms are but a ‘thin slice’ of human possibility. For the vast bulk of human history, mankind lived in small, mobile groups roving across the world’s tropical forests, savannahs and prairies. From Diamond’s perspective, these societies represent ‘thousands of millennia-long natural experiments in organizing human lives’; and while we cannot repeat them, he argues, we can at least take heed of their positive aspects, incorporating them into our lives where possible, and campaigning for society-wide changes if necessary.

Using his own experience in New Guinea, an area of considerable cultural diversity (‘a window on the world as it was until a mere yesterday’), supplemented with ethnographic studies covering other regions, Diamond sifts the good from the bad in