Buddhi
Intuitional body (6)
Buddhi — the intuitional principle, the seat of unitive wisdom and direct apprehension. Above the discursive mind (manas) and below the pure spirit (ātman). Besant calls it the 'spiritual soul', the principle through which the human is consciously at one with all life. In Leadbeater's clairvoyant report the buddhic plane is rendered in iridescent blue; the shift from causal to buddhic marks the threshold between the human and the divine in the Theosophical hierarchy.
Point 6 of 7 in Theosophy — Seven Subtle Bodies
Cross-tradition overlaps
No overlapping points are registered for this point.
Sources
Blavatsky, The Secret Doctrine (primary_canonical)
Blavatsky, The Secret Doctrine, Adyar edition, vol. I, pp. 153–159, 'The Planetary Divisions and the Human Principles' and 'Transmigrations of the Ego,' places buddhi in the upper triad with atman and manas; the passage supports buddhi as a spiritual principle, not a coloured organ.
Besant, The Ancient Wisdom (primary_canonical)
Besant, The Ancient Wisdom, ch. IV, 'The Devachanic World,' treats buddhi as the spiritual principle associated with the higher, unitive consciousness; chapter title and numbering follow the 1897 work's standard edition.