Aurobindo’s concept of the “physical mind” may seem pretty strange. It doesn’t mean anything technically physical but rather the level of the mind “closest” to the physical body that translates the mind’s most basic repetitive habits into the constitutional qualities of the vital and physical bodies. Though there are certainly a lot of connotations one may not get without reading all of Synthesis of Yoga, he uses the term pretty simply and uniformly throughout his letters to his disciples. He basically just transposed the three gunas of samkhya into the intertwined actions of the levels of the lower mind. Like the three gunas, the conceptual mind, the vital mind, and the physical mind are always acting but in different proportions.
The physical mind is basically the mechanical mind, the tamas guna, inertia, repeating the habits of thought picked up from the world, modified by the person’s nature and regurgitated endlessly like a background buzz of bullshit. Or even more concretely, it is all the shit in your mind that persists even after the conceptual and vital mind are quite. For me it is always music playing endlessly that I have to be patient to shut off completely. He also likens it to a screen that prevents the final descent of the higher levels of spiritual mind and shakti at each level of transformation. Basically it is the dull inertia of the mind that takes root at each stage of transformation preventing the next higher stage from taking root and becoming the new automatic habit of the lower nature. As the physical mind takes on progressively higher organizing principles as its foundational pattern it becomes the all important grounding force of repetition that solidifies each new attainment with the power of established instinct in the mind, which then can take root in the vital and physical nature. Without its protection we would be open to any force coming along an taking us over, so I feel it like a defense against all that I am not ready to handle.
Steiner doesn’t have as rich a psychology as AUrobindo but I think a clearer picture of how new habits are laid down into our body/bodies through our entire life, thought and action. Granted his style is more in the vein of the abstruse German philosopher, which he was after all, and Aurobindo retains a rather English sense of pragmatic utility from his education and upbringing. But Steiner makes very explicit the interrelationships that are lacking in Eastern Yoga, or vague even in Integral Yoga. Not completely lacking, because I believe it was there in the very esoteric traditions of India and Tibet, which Theosophy claims was its source after all. But an explicit understanding of the role of integration is so hidden that it leads someone like Ken Wilber to claim it entirely a discovery of modern psychology.
Though he is wrong, as usual (he even states there were no psychological stages at all in traditional systems only a series of progressing states), he does have a point: we hear very little about complex dependencies between centers or between states and stages of consciousness. For the most part the emphasis is on linear, mostly inner progress of consciousness according to separate lines of development (even if the yoga is the yoga of action, what matters for the karma yogi is not so much the outer subjectivity and relations of the yogi but the inner consciousness of the subject as he acts).
I find it odd that the interrelationships between chakras in popular yoga is hardly mentioned, and yoga in general tends to frame the whole transformational movement as a series of “openings”. Each center is often conceived in isolation. In aurobindo’s yoga, the centers are opened up together because he foregrounds their dependence and integration. But in all his verbose classifications I don’t think he gives as clear of an explanation and visualization of how each center and stage depends on the whole life of the person. Each center doesn’t just need to open. In fact too open too soon is a problem, as I stated before. We have defenses and blocks for a reason. Too often the method obsessed yogi forces open a center which leads to an imbalance in the overall character that can be disastrous. Steiner on the other hand makes clear in that short book mentioned that each center crystallizes according to the overall integral development of the person. Each petal of each lotus depends on a network of interrelated developments.
Aurobindo’s Integral Yoga is basically the top down occult path that Theosophy claims to have gotten from masters in the East. I do think that although Theosophy/Steiner are occult paths and share a lot with Western occultism, they are very different than the hermeticists that as Ryan mentioned, are much more method and magic obsessed. In contrast Theosophy/Anthroposophy/Integral Yoga are all mostly the same path of spiritual progress through complete surrender to the Divine. Integration follows suit from that impulse, and if integration is sought after without devotion, you get, like Mr. Wilber, a lot of errors and a major psychological problem. Too many possibilities. No spiritual center. To paraphrase Wilber himself, you just get a heap, not a whole.
But that inner guidance can direct us to helpful material in the world. I find something of value in everything. The I Ching is by far my best guide. And the Chinese tradition in general is particularly helpful at the vital level where the Indian yoga falls short. I believe this is why they do not focus on the chakras, but take as a first crucial grounding step the whole lower set of centers as a group (dan tien) to be channelled into an integrated circuit that balances every center. Gurdjieff as well groups them all together as the movement center. Instead of hatha yoga with its linear motions forcing open isolated centers, both chinese alchemy/tai chi and Gurdjieff’s movements all emphasize integrated movement. In chen tai chi in particular, motion is nonlinear, a cycle within a cycle, a pulse and a rotation, a reciprocal exchange between centers that mirrors the physics I spend my time on these days (inspired by Dewey Larson’s Reciprocal System). Practicing chen tai chi is a great way to feel at the vital and physical levels what surrender is all about. In the dance with the other you can see concretely exactly where you are not surrendering, and clearly understand why surrender is not a passive state but an intelligent sensitivity to every meaningful relationship around you.