| 释义 |
hexagram|ˈhɛksəgræm|
[f. hexa- + Gr. γράµµα line, letter.]
1. A figure formed by two intersecting equilateral triangles, each side of the one being parallel to a side of the other, and the six angular points coinciding with those of a hexagon.
1871B. Taylor Faust (1875) I. 256 Paracelsus ascribes a similar degree of virtue to the hexagram.
2. Geom. A figure of six lines.
The term is spec. applied to: (a) Pascal's mystic hexagram, which is formed by lines joining six points on a conic, and has the property that the intersections of the first and fourth, the second and fifth, and the third and sixth of these lines lie on one straight line; (b) Brianchon's hexagram, which is a six-sided figure circumscribed about a conic, and has the property that the three lines joining opposite angles intersect in one point.
1863R. Townsend Mod. Geom. I. 145 In a hexastigm or hexagram every triangle determined by three points or lines is said to be the opposite of that determined by the remaining three. 1885Encycl. Brit. XVIII. 338 He [Pascal] established the famous theorem that the intersections of the three pairs of opposite sides of a hexagon inscribed in a conic are collinear. This proposition, which he called the mystic hexagram, he made the keystone of his theory.
3. In Chinese literature, one of the sixty-four figures, consisting each of six parallel (whole or divided) lines, which form the basis of the ‘Yih-king’ or ‘book of changes’.
1882R. K. Douglas China xix. 359 Following each hexagram occur a few sentences of the original text. 1882Athenæum 2 Sept. 296/3 The ‘Yi King’, or ‘Book of Changes’, consists of sixty-four hexagrams, the component parts of which are whole or divided lines, placed one over the other in a certain fanciful order, and called by a name which in its turn suggests an explanation found in the text. |