《论衡·卷二十三·四讳篇》
正月是一年的开始，五月是阳气最旺盛的时候，孩子在这种月份出生，精气旺盛热烈，压过了父母，父母经受不起，将会受到他的伤害。
夫正月岁始，五月盛阳，子以生，精炽热烈，厌胜父母，父母不堪，将受其患。
January is the beginning of the year, May is the month with the strongest yang energy, children born in such a month, with vigor and enthusiasm, will suppress their parents, and parents can't bear it, and will be hurt by him.