From 8 December 1915 letter to Bertrand Russell,
page 470 of The Letters of D.H. Lawrence: June 1913-October 1916.
I have been reading Frazer’s Golden Bough and Totemism and Exogamy. Now I am convinced of what I believed when I was about twenty—that there is another seat of consciousness than the brain and nerve system: there is a blood-consciousness which exists in us independently of the ordinary mental consciousness, which depends on the eye as its source or connector. There is the blood-consciousness, with the sexual connection, holding the same relation as the eye, in seeing, holds to the mental consciousness. One lives, knows, and has one’s being in the blood, without any reference to nerves and brain. This is one half of life, belonging to the darkness. And the tragedy of this our life, and of your life, is that the mental and nerve consciousness exerts a tyranny over the blood-consciousness, and that your will has gone completely over to the mental consciousness, and is engaged in the destruction of your blood-being or blood-consciousness, the final liberating of the one, which is only death in result. Plato was the same. Now it is necessary for us to realise that there is this other great half of our life active in the darkness, the blood-relationship: that when I see, there is a connection between my mental-consciousness and an outside body, forming a precept; but at the same time, there is a transmission through the darkness which is never absent from the light, into my blood-consciousness: but in seeing, the blood-percept is not strong. On the other hand, when I take a woman, then the blood-percept is supreme, my blood-knowing is overwhelming. There is a transmission, I don’t know of what, between her blood and mine, in the act of connection. So that afterwards, even if she goes away, the blood-consciousness persists between us, when the mental consciousness is suspended; and I am formed then by my blood-consciousness, not by my mind or nerves at all.