Women should marry when they are about eighteen years of age, and men at seven and thirty; then they are in the prime of life, and the decline in the powers of both will coincide.
 Aristotle, Politics (4th century BC). copy citation

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Author Aristotle
Source Politics
Topic age power
Date 4th century BC
Language English
Reference
Note Translated by Benjamin Jowett
Weblink http://classics.mit.edu/Aristotle/politics.html

Context

“for women who marry early are apt to be wanton; and in men too the bodily frame is stunted if they marry while the seed is growing (for there is a time when the growth of the seed, also, ceases, or continues to but a slight extent) . Women should marry when they are about eighteen years of age, and men at seven and thirty; then they are in the prime of life, and the decline in the powers of both will coincide. Further, the children, if their birth takes place soon, as may reasonably be expected, will succeed in the beginning of their prime, when the fathers are already in the decline of life, and have nearly reached their term of three-score years and ten.” source