There is no logical correlation between chronological age and wisdom. Wisdom is something you seek. If you do not value it, if you do not seek it out, you will not find it.
Wisdom is not genetically endowed nor is it hereditary. Wisdom is not distributed proportionate to birth order. While youth has a strong correlation with beauty so too does ignorance; ignorance can linger long after youth and beauty have fled.
Chronological age, relative age, and birth order logically does nothing to account for the distribution of wisdom, and leads to several patently false assumptions:
I am old, therefore I am wise.
I am older than you, friend, therefore I am wiser than you.
I was born before you, brother, therefore I am wiser than you.
Primogeniture and other such laws of inheritence involves the distribution of an estate – not wisdom. Property as a concept is not universal, but where it is, insipid fools can inherit vast estates. The rich man is no more deserving of his inheritence than the poor man is his; but the rich man likes to think himself superior, blessed, or even chosen by God; and fools buy into such nonsense. Inheritence is an invention of man.
The rich man who inherits a great estate is loathe to question or even discuss his own worthiness of it; and for the man of little estate, “me-too-ism” prevents him from questioning the order and magnitude of things and makes him ever so grateful for the bone he is thrown.
Throughout human history devastating wars have been fought between heirs and bastards; but only a handful of intellects ever dared to question inheritence as a concept.