Evolution acts at an individual level
The orthodox view of evolution is that it must act at an individual level. Looking at it from a XX-century scientist, that would mean that it acts at a gene-level[@dawkins2016The selfish gene: 40th anniversary edition, Chapter 1].
I shall argue that the fundamental unit of selection, and therefore of self-interest, is not the species, nor the group, nor even, strictly, the individual. It is the gene, the unit of heredity.
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