Sri Aurobindo on Astrology

Even if the prediction were accurate according to the horoscope it need not fulfil itself, because by entering the spiritual life one opens to a new force which can change one's destiny. (August 22, 1937)

It does not seem to me established that the stars determine the future - though that is possible, but it does look as if they indicate it - or rather, some certitudes and potentialities of the future. Even the astrologers admit that there is another element of determination in man himself which limits the field of astrological prediction and may even alter many of its ascertained results. There is a very tangled and difficult complex of forces making up any determination of things in the world and when we have disentangled one thread of the skein and follow it we may get many striking results, but we cannot rely on it as the one wholly reliable clue. The mind’s methods are too rigid and conveniently simple to unravel the true or whole truth whether of the Reality or of its separate phenomena.

Astrology? Many astrological predictions come true, quite a mass of them, if one takes all together. But it does not follow that the stars rule our destiny; the stars merely record a destiny that has been already formed, they are a hieroglyph, not a Force, - or if their action constitutes a force, it is a transmitting energy, not an originating Power. Someone is there who has determined or something is there which is Fate, let us say; the stars are only indicators.
The astrologers themselves say that there are two forces, daiva and purushakara, fate and individual energy, and the individual energy can modify and even frustrate fate. Moreover, the stars often indicate several fate-possibilities; for example that one may die in mid-age, but that if that determination can be overcome, one can live to a predictable old age. Finally, cases are seen in which the predictions of the horoscope fulfil themselves with great accuracy up to a certain age, then apply no more. This often happens when the subject turns away from the ordinary to the spiritual life. If the turn is very radical, the cessation of predictability may be immediate; otherwise certain results may still last on for a time, but there is no longer the same inevitability.
This would seem to show that there is or can be a higher power or higher plane or higher source of spiritual destiny which can, if its hour has come, override the lower power, lower plane or lower source of vital and material fate of which the stars are indicators. I say vital because character can also be indicated from the horoscope much more completely and satisfactorily than the events of the life.

There must therefore be two elements, Karma as an instrument, but also the secret Consciousness and Will within working through the mind, life and body as the user. Fate, whether purely mechanical or created by ourselves, a chain of our own manufacture, is only one factor of existence; Being and its consciousness and its will are a still more important factor.
In Indian astrology which considers all life-circumstances to be Karma, mostly predetermined or indicated in the graph of the stars, there is still provision made for the energy and force of the being which can change or cancel part or much of what is so written or even all but the most imperative and powerful bindings of Karma. This is a reasonable account of the balance: but there is also to be added to the computation the fact that destiny is not simple but complex; the destiny which binds our physical being, binds it so long or in so far as a greater law does not intervene. Action belongs to the physical part of us, it is the physical outcome of our being; but behind our surface is a freer Life-power, a freer Mind-power which has another energy and can create another destiny and bring it in to modify the primary plan, and when the soul and self emerges, when we become consciously spiritual beings, that change can cancel or wholly remodel the graph of our physical fate.
Karma, then, - or at least any mechanical law of Karma, - cannot be accepted as the sole determinant of circumstances and the whole machinery of rebirth and of our future evolution.