Literary notes about tetrad (AI summary)
The term "tetrad" is employed across literary genres to signify a complete or fundamental grouping of four components. In scientific narratives, it designates specific structures—whether referring to molecular valences, cellular groupings, or arrangements in botany and genetics [1][2][3]. Meanwhile, in more philosophical or mystical writings, the tetrad assumes an emblematic role, representing perfection or a primordial order as seen in allusions to elemental balance or sacred schemes like the Holy Tetrad [4][5][6]. This versatile usage underscores how a quartet, whether literal or symbolic, serves as an archetype for wholeness and symmetry throughout literature.
- An element having a valence of one is a monad; of two, a dyad; three, a triad; four, tetrad; five, pentad; six, hexad, etc.
— from An Introduction to Chemical Science by Rufus P. (Rufus Phillips) Williams - Thus the terms a diplococcus, a tetrad, a streptococcus, etc., are common, meaning a bacterium of the cell form and cell grouping indicated.
— from The Fundamentals of Bacteriology by Charles Bradfield Morrey - Each a single cell like the preceding, but here only one tetrad in a sporangium ripens, so that each contains only four spores.
— from Ancient Plants Being a Simple Account of the past Vegetation of the Earth and of the Recent Important Discoveries Made in This Realm of Nature by Marie Carmichael Stopes - That the tetrad should be considered to be thus complete, reminds one of the four elements, the physical and the chemical, the four continents, &c.
— from Hegel's Lectures on the History of Philosophy: Volume 1 (of 3) by Georg Wilhelm Friedrich Hegel - The adorable tetractys, or tetrad, is the formula of God; which, again, is reducible into, and is, in reality, the same with, the Trinity.
— from Specimens of the Table Talk of Samuel Taylor Coleridge by Samuel Taylor Coleridge - An oath used by the Pythagoreans, who regarded the tetrad, the sum of the first four numbers, as symbolical of all proportion and perfection; cf.
— from The Works of the Emperor Julian, Vol. 2 by Emperor of Rome Julian
