satadha kalpitasya ca
bhago jivah sa vijneya
iti caha para srutih
bala-agra—the tip of a hair; sata-bhagasya—of one hundredth; sata-dha—into one hundred parts; kalpitasya—divided; ca—and; bhagah—minute portion; jivah—the living entity; sah—that; vijneyah—to be understood; iti—thus; ca—and; aha—have said; para—chief; srutih—Vedic mantras.
" 'If we divide the tip of a hair into one hundred parts and then take one part and divide this into another one hundred parts, that ten-thousandth part is the dimension of the living entity. This is the verdict of the chief Vedic mantras.'
The first three padas of this verse from the Pancadasi Citradipa (81) are taken from the Svetasvatara Upanisad (5.9).
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