Sri Aurobindo reiterates that it cannot be a fact that the soul is entirely subject to the mechanical working of an inflexible law of Karma. Thus, the law of Karma can only be part of a much larger process that includes higher laws that bring a certain amount of flexibility and conscious will into the actual working out of future lives and events. There is a secret Will which operates behind the law of Karma and provides the consent and support of the psychic being, the soul in manifestation, to the karmic mechanismus. “That secret Will is not mechanical, but spiritual; the guidance comes from an Intelligence which may use mechanical processes but is not their subject. Self-expression and experience are what the soul seeks by its birth into the body; whatever is necessary for the self-expression and experience of this life, whether it intervenes as an automatic outcome of past lives or as a free selection of results and a continuity or as a new development, whatever is a means of creation of the future, that will be formulated: for the principle is not the working out of a mechanism of Law, but the development of the nature through cosmic experience so that eventually it may grow out of the Ignorance. 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.”
Karma may be a strong factor in the result, but it can be modified or overcome by the spiritual Will, exercising forces operating on a different plane and with a different power than Karma. “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.”
Sri Aurobindo, The Life Divine, Book 2, Part 2, Chapter 22, Rebirth and Other Worlds; Karma, the Soul and Immortality
Sri Aurobindo Studies 