When we take the mind to its furthest levels of development, when we integrate the action of a purified sense-mind, a rational and detail-oriented logical intellect and the working of imagination properly integrated into the mind’s action, we find that we have reached the limits of mentality, but remain nevertheless locked into the framework of the external world. We may have a greater power of action based on a more focused and powerful intellectual capability, and we may be able to understand the manifested universe more clearly, but at the end, we find that this form of knowing does not provide us any definitive answers to the ultimate questions of existence, meaning and purpose.
It is necessary to go beyond the mental range of awareness to gain the insights that can respond to these inquiries. A shift of the standpoint from the mental to something greater and higher, to the spiritual standpoint, is required in order to know the truth of the Spirit. The Taittiriya Upanishad alludes to this when it declaims: “The Bliss of the Eternal from which words turn back without attaining and mind also returneth baffled…” (Brahmanandavalli, Ch. 9, in The Upanishads, Sri Aurobindo, pg. 274)
Sri Aurobindo observes: “It is more and more perceived that the knowledge of phenomena increases, but the knowledge of reality escapes this laborious process. A time must come, is already coming when the mind perceives the necessity of calling to its aid and developing fully the intuition and all the great range of powers that lie concealed behind our vague use of the word and uncertain perception of its significance. In the end it must discover that these powers can not only aid and complete but even replace its own proper action. That will be the beginning of the discovery of the supramental energy of the spirit.”
Sri Aurobindo, The Synthesis of Yoga, Part Four: The Yoga of Self-Perfection, Chapter 23, The Supramental Instruments — Thought-process , pp. 823-824