In order to define what nourishment is according to Āyurveda we need to understand the context of Āyurveda as both a medical system and world vision. Āyurveda is based on the concept that the universe and everything manifested within it is intelligent. This idea is fundamentally different than the current accepted vision. The modern view prefers to divide and separate living entities into pieces in order to understand them, which in effect, kills any intelligent principle within the entity. Viewing the universe and everything in it as intelligent implies the necessity to keep individual entities under study as an integral unit, rather than dividing them into pieces.
To understand or study Āyurveda this basic precept of intelligence needs to be taken into account - even if it is not accepted. Āyurvedic texts like the Caraka Samhita or Bhāvaprakāśa indicate through Sūtra or Sanskrit verse that this concept is the basis from which to under the whole system. For example, this text from one of the six classic textbooks of Āyurveda states clearly that all manifest matter (including humans) is derived from consciousness, or intelligence.
"Ātma is radiance in the form of pure consciousness that is eternal, unchanging and that has no desires or attributes ; when combined with primordial matter it acquires qualities and creates the manifest world."
Bhāvaprakāśa, Sṛṣṭi Prakaraṇa, 3
If we establish that Āyurveda views the human body as an intelligent entity then we must also try to define nutrition and nourishment according to this fundamental concept. Viewing nutrition and nourishment from the point of view of individual components - such as protein, fats, vitamins, etc. - will not be applicable to Āyurveda. The necessity to view nourishment as a holistic phenomenon rather than a sum total of individual building blocks is essential for the Āyurvedic definition of nourishment.
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