Mundaka Upanishad — The Higher and Lower Knowledge
The Mundaka Upanishad's distinction between the Higher Knowledge (Para Vidya — knowledge of Brahman) and Lower Knowledge (Apara Vidya — all other sciences) establishes the supreme place of Brahma Vidya in the hierarchy of knowing.
The Mundaka Upanishad opens with the question: 'By knowing what, O Revered One, does all this become known?' Angiras answers by distinguishing Para Vidya (higher knowledge — knowledge of Brahman, by which all else is known) from Apara Vidya (lower knowledge — the four Vedas, phonetics, ritual, grammar, etymology, meter, and astronomy — all the sciences and arts). This distinction is the Upanishads' most explicit statement of the hierarchy of knowledge: all sciences deal with Nama Rupa (name and form) within the conventional world, while Brahma Vidya reveals the ground from which all Nama Rupa arises. The Mundaka is also the source of two major Mahavakyas (Satyam jnanam anantam Brahma and the Brahma Jigyasa instructions) and the famous statement 'Satya meva jayate' (Truth alone triumphs) — adopted as India's national motto.
Two kinds of knowledge must be known — the higher (Para Vidya) and the lower (Apara Vidya). The higher is that by which the Imperishable is known.
Philosopher Michael Polanyi's 'The Tacit Dimension' — arguing that all explicit knowledge rests on a foundation of tacit, non-explicit knowing that cannot itself be fully articulated — parallels the Mundaka's distinction: Apara Vidya (explicit sciences) all depend on the tacit ground of Para Vidya (the knowing consciousness itself).
Mundaka Upanishad