Ichiyousei - Ichiyousei

...It also means the arrival of spring or the end of misfortune and the return of good fortune. As it is also called "Yi Yang Sheng," it is based on the fact that Yi Yang (the symbol of yin) has sprouted again at the bottom of the "Fuku" hexagram in the "I Ching." The opposite of this is the summer solstice of "Yi Yin Sheng," which is the "Kou" hexagram in the "I Ching." ...

*Some of the terminology explanations that mention "Ichiyousei" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…また，春の到来や凶事が去って吉事がふたたびもどって来ることをいう。〈一陽生〉ともいうように，《易経》の復（ふく）の卦（か）の最下段に，一陽(は陽，は陰のシンボル)が復（ふたた）び芽生えたことにもとづく。この逆が〈一陰生〉の夏至，《易》でいえば姤（こう）の卦である。…

※「一陽生」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報