Time is the great equalizer – it takes from us our youth and replaces it with experience.  As the exuberance of young ideals become distant memories, the realism of life’s journey grants us insight and wisdom.  And it’s always easier for elders to look back and remember how it was; much easier than it is for children to look ahead and understand how it really is.  But try telling that to a teenager.  In that vein, here are some thoughts on youth from some of the great minds of the past 2500 years:

“The deepest definition of youth is life as yet untouched by tragedy.” 
Alfred North Whitehead

“To get back my youth I would do anything in the world, except take exercise, get up early, or be respectable.”     
Oscar Wilde 

“There's nothing that keeps its youth,
So far as I know, but a tree and truth.”     
Oliver Wendell Holmes

“Youth is a wonderful thing. What a crime to waste it on children.”     
George Bernard Shaw

“Young people are in a condition like permanent intoxication, because youth is sweet and they are growing.”
Aristotle

“Praise youth and it will prosper.”   
Irish Proverb

“Don't laugh at a youth for his affectations; he is only trying on one face after another to find his own.”     
Logan Pearsall Smith

“Keep true to the dreams of thy youth.”     
Friedrich von Schiller

“Youth cannot know how age thinks and feels. But old men are guilty if they forget what it was to be young.”     
J. K. Rowling 

“The heads of strong old age are beautiful beyond all grace of youth.”     
Robinson Jeffers

“Never suffer youth to be an excuse for inadequacy, nor age and fame to be an excuse for indolence.”     
Benjamin Haydon

“Age is opportunity no less
Than youth itself, though in another dress,
And as the evening twilight fades away
The sky is filled with stars, invisible by day.”   
Henry Wadsworth Longfellow

“In youth we learn; in age we understand.”
Marie Ebner von Eschenbach

“Whoso neglects learning in his youth, loses the past and is dead for the future.”     
Euripides

“Make wisdom your provision for the journey from youth to old age, for it is a more certain support than all other possessions.”     
Bias

“We have some salt of our youth in us.”     
William Shakespeare

“The foundation of every state is the education of its youth.”     
Diogenes Laertius

“The pride of youth is in strength and beauty, the pride of old age is in discretion.”     
Democritus

“It is a youthful failing to be unable to control one's impulses.”     
Seneca

“The surest way to corrupt a youth is to instruct him to hold in higher esteem those who think alike than those who think differently.”     
Friedrich Nietzsche

“Youth, which is forgiven everything, forgives itself nothing: age, which forgives itself everything, is forgiven nothing.”     
George Bernard Shaw

“If youth only knew: if age only could.”     
Henri Estienne

“Childhood, noun: The period of human life intermediate between the idiocy of infancy and the folly of youth - two removes from the sin of manhood and three from the remorse of age.”     
Ambrose Bierce

“What a price we pay for experience, when we must sell our youth to buy it.”    
Javan

“I do beseech you to direct your efforts more to preparing youth for the path and less to preparing the path for the youth.”
Ben Lindsey (and most heartily endorsed by yours truly)