The structure and physiology of the brain furnish no explanation of the psychic process. ~Carl Jung, The Undiscovered Self, Page 33.

A psychology that treats the mind as an epiphenomenon would better call itself brain-psychology, and remain satisfied with the meager results that such a psycho-physiology can yield. The mind deserves to be taken as a phenomenon in its own right; there are no grounds at all for regarding it as a mere epiphenomenon, dependent though it may be on the functioning of the brain. One would be as little justified in regarding life as an epiphenomenon of the chemistry of carbon compounds. – “On Psychic Energy” (1928). In CW 8: The Structure and Dynamics of the Psyche. pp.10

The prana discipline has practically the same effect. It concentrates the psychic energy upon the inner ways in which the prana flows. The localization in the brain is doubtful, but in general it is correct to assume that the unconscious processes are chiefly located in the lower centres of the brain from the thalamus downwards. ~Carl Jung, Letters Vol. 1, Pages 497-498.

Since the time of the old Gnostics, the serpent has been the symbol for the brain and its appendages; that is, for the lower centres of the brain and for the spinal cord, partly on account of its shape, but also from introspective reasons. ~Carl Jung, ETH, Alchemy, Page 216.

One could say, in a certain sense, that the unconscious was the invisible, psychical part of the tangible and visible nervous system, just as one might say consciousness was the invisible part of the brain. ~Carl Jung, ETH, Alchemy, Page 216.

This disproves the theory that a child’s mind is a tabula rasa, for it shows us that the unconscious is no empty surface, but a prepared ground; the brain is complete with the history of the world and every child is born with an unconscious assumption of the world. ~Carl Jung, ETH Lecture V, Page 27.

Archetypes are systems of readiness for action, and at the same time images and emotions. They are inherited with the brain structure—indeed, they are its psychic aspect. ~Carl Jung, CW 10, Page 31.

After a stroke general debilitation or senile depression can occur. If the brain is damaged, consciousness can slip back many levels. The real personality has then departed; what remains carries on the fight against death. Conflicts do not reach the whole person anymore and are therefore not real conflicts any longer. ~Carl Jung, Jung-Ostrowski, Page 16.

In the light of this view the brain might be a transformer station, in which the relatively infinite tension or intensity of the psyche proper is transformed into perceptible frequencies or “extensions.” ~Carl Jung, Letters Vol. II, Pages 43-47.

The question of brain localization is an extremely delicate one, because when you destroy a certain part of the brain you destroy a certain function. ~Carl Jung, Letters Vol. II, Pages 159-161.

There is even no absolute certainty about the psyche being definitely dependent upon the brain since we know that there are facts proving that the mind can relativize space and time, as the Rhine experiments and general experience have proved sufficiently. ~Carl Jung, Letters Vol. II, Pages 159-161.

I should not worry about all this localization talk. It’s practically all foolishness, and a remnant of the old brain mythology like the explanation of sleep through the contraction of the ganglia, which is by no means more intelligent than the localization of the psyche in the pituitary gland. ~Carl Jung, Letters Vol. II, Pages 159-161.

It is on the contrary an excellent demonstration of Marxist materialism: mescalin is the drug by which you can manipulate the brain so that it produces even so-called “spiritual” experiences. That is the ideal case for Bolshevik philosophy and its “brave new world.” ~Carl Jung, Letters Vol. II, Pages 222-224.

As long as you [Victor White] do not identify yourself with the avenging angel, I can feel your humanity and I can tell you that I am really sorry for my misdeeds and sore about God’s ways with the poor anthropoids that were meant to have a brain enabling them to think critically. ~Carl Jung, Letters, Vol. II, Pages 238-243.

But we do know that warm-bloodedness and a differentiated brain were necessary for the inception of consciousness, and thus also for the revelation of meaning. ~Carl Jung, Letters Vol. II, Pages 493-496

But in these days we live by our brains alone and ignore the very definite laws of our body and the instinctive world. ~Carl Jung, Letters Vol. II, Page 567

We are not convinced that our thoughts are original beings that walk about in our brains, and we invent the idea that they are powerless without our gracious creative act; we invent this in order not to be too much influenced by our thoughts. ~Carl Jung, 1925 Seminar, Page 82

Obviously there is no law to prove that this is so, but we cannot assume that the products of our brains do not derive from nature; therefore I see no reason why we would not find astonishingly true things in the thought of the ancient sages, such as the I Ching represents. ~Carl Jung, 1925 Seminar, Page 84

It is as though in men the animal likeness stopped at the spinal cord while in women it extends into the lower strata of the brain, or that man keeps the animal kingdom in him below the diaphragm, while in women it extends throughout her being. ~Carl Jung, 1925 Seminar, Page 124

When it comes to the rather delicate task of locating the collective unconscious, you must not think of it as being compassed by the brain alone but as including the sympathetic nervous system as well. ~Carl Jung, 1925 Seminar, Page 140

We cannot repeat this distinction too often, for when I have referred to the collective unconscious as “outside” our brains, it has been assumed that I meant hanging somewhere in mid-air. ~Carl Jung, 1925 Seminar, Page 141

The creative substratum is everywhere this same human psyche and this same human brain, which, with relatively minor variations, functions everywhere in the same way. ~Carl Jung, CW 5, Page xxix

He [Jung] said he had for a long time thought that the brain stem was important in our thinking life and how interested he was that the corpora quadrigemina, the four bodies, was the area, for it confirmed his idea of the importance of the square and the circle as symbols. ~E.A. Bennet, Meetings with Jung, Page 157