Tis about when one's mind is mature. The young are impatient, the novelty of their lives causes them to act irrationally while they chase fleeting desires.

[So basically similar to those he referred to as "shemlen". Might explain some of his irritation, seeing as he was surrounded by the equivalent of Elvhen teenager for his foreseeable future.]

It takes a few centuries for one to see past such petty things and start to focus on something worthwhile.