‖ tetractys
(tɪˈtræktɪs)
Also 8 tetrachty(s, 9 tetraktys.
[a. Gr. τετρακτύς.]
A set of four; the number four; esp. the Pythagorean name for the sum of the first four numbers (1 + 2 + 3 + 4 = 10) regarded as the source of all things.
| 1603 Holland Plutarch's Mor. 1317 That famous quaternarie of theirs, named Tetractys, which consisteth of foure nines, and amounteth to thirtie sixe, was their greatest oth. 1653 H. More Conject. Cabbal. Pref. (1713) 4 The Pythagoreans Oath, swearing by him that taught them the mystery of the Tetractys, or the number Four. a 1774 Tucker Lt. Nat. (1834) II. 415 Pythagoras had his tetrachty, his mystic numbers, his symbols. 1865 Grote Plato I. i. 12 note, The tetraktys (consecrated as the sum total of the first four numbers 1 + 2 + 3 + 4 = 10). |
Hence teˈtractysm, the Pythagorean doctrine of the tetractys.
| 1846 T. W. Jenkyn Baxter's Wks. Pref. 50 Those who understand..what Tetractysm was to the Pythagoreans will..comprehend what Triadism was to Baxter. |