F4 — fourth tone
341.33 Hz · 4:3 diatessaron
The upper-abdominal point represents F4 at approximately 341.33 Hz, calculated from the 4:3 diatessaron ratio over C4 = 256 Hz. The harmonic interval is source-grounded, but its placement at the centre of the trunk is a modern teaching convention rather than a claim about will, digestion, or a solar organ.
Point 5 of 7 in Pythagorean Harmonic Body
Cross-tradition overlaps
No overlapping points are registered for this point.
Sources
Iamblichus, Life of Pythagoras (primary_canonical)
Chapters XV and XXV discuss musical education, purification, and the ordering of the soul; chapter XXVI recounts the discovery of harmonic ratios and identifies diapason, diapente, and diatessaron. The text supports music-and-ratio doctrine, not a seven-point body coordinate map.
Walter Burkert, Lore and Science in Ancient Pythagoreanism (scholarly_modern)
Burkert provides modern historical analysis of Pythagorean number, music, cosmology, and the limits of later doxographic accounts; it is used here to keep the body projection distinct from ancient evidence.