A sage should observe three stages of self-discipline.
In youth, his physical capability is not fully settled and he should guard against lust.
In his prime when his physical capability is solid, he should guard against contention.
In old age his physical capability is declining, he should guard against greed.
圣人学会三戒：
少之时，血气初定，戒之在色；
壮年也，血气方刚，戒之在争；
其老也，血气渐衰，戒之在得。
– Master Jun Hong Lu, Words of Wisdom Volume 6
