If youth knew; if age could.

Invention is the talent of youth, and judgment of age…

In youth we learn; in age we understand.

Youth is the time of getting, middle age of improving, and old age of spending.

I am beginning to understand the true difference between youth and age. Young people have time to make plans and think of new ideas. Older people need their whole energy to keep up with what’s already been set in motion.

There is so much adventure that only a youth can experience. Youth is not the time to languish in pleasure - youth is the time for exploration and adventure

Youth may outrun the old, but not outwit.

In youth it is the outward aspect of things that most engages us; while in age, thought or reflection is the predominating quality of the mind. Hence, youth is the time for poetry, and age is more inclined to philosophy. In practical affairs it is the same: a man shapes his resolutions in youth more by the impression that the outward world makes upon him; whereas, when he is old, it is thought that determines his actions.

Youth, n. The Period of Possibility, when Archimedes finds a fulcrum, Cassandra has a following and seven cities compete for the honor of endowing a living Homer.

Knowledge in youth is wisdom in age.

Youth is a period of missed opportunities.

A youth is to be regarded with respect. How do we know that his future will not be equal to our present? If he reach the age of forty or fifty, and has not made himself heard of, then indeed he will not be worth being regarded with respect.

Youth is wholly experimental.

Youth is not an age thing. It's a quality. Once you've had it, you never lose it.