In 2008 Stephen Pinker’s genome was sequenced and pub­licly released as part of the Per­sonal Genome Project. In light of this, Pinker argues that even though our genes greatly influ­ence our behav­iour, they don’t deter­mine who we are, con­clud­ing that “even when the effect of some gene is indu­bitable, the sheer com­plex­ity of the self will mean that it will not serve as an ora­cle on what the per­son will do.”

The scare word “deter­min­ism” [should not] get in the way of under­stand­ing our genetic roots. For some con­di­tions, like Huntington’s dis­ease, genetic deter­min­ism is sim­ply cor­rect: every­one with the defec­tive gene who lives long enough will develop the con­di­tion. But for most other traits, any influ­ence of the genes will be prob­a­bilis­tic. Hav­ing a ver­sion of a gene may change the odds, mak­ing you more or less likely to have a trait, all things being equal, but as we shall see, the actual out­come depends on a tan­gle of other cir­cum­stances as well.