When the twenty-two-year-old Sylvia Plath (October 27, 1932–February 11, 1963) wrote to her mother one bleak January day, both women were wading through a darkness of the soul. Science was only just beginning to hone the tools with which to begin dissecting the elemental mystery of what makes us who we are: how much of our psychology and what we experience as our personhood — whether we call it self or soul or spirit — is a product of our physical constitution, of the particular biochemical processes coursing through our particular infrastructure of matter that we experience as our body. Neuroscience was then an infant science — it still is — and the helix of heredity had just been discovered, hinting at the promise of new clarity on the ancient puzzlement of nature versus nurture, new insight into how much of our psychology is a biological inheritance and how much an ongoing composition continually revised by the confluence of chance and choice we call experience.

Lês en sjoch fierder by Maria Popova op Brain Pickings