Are you a snob, or a lethargic?

"...childhood and youth are vanity. Remember now thy Creator in the days of thy youth [before old age comes and]...the dust return to the earth as it was: and the spirit return unto God Who gave it. Vanity of vanities, saith the preacher, all is vanity." Ecclesiastes 11:10b; 12:1a,7,8

There are many people who live for an age.
There are (as Lewis called them) chronological snobs: those who believe what is good is the new and young and fresh, full of life and youth and progress. The old is merely boundaries that limit potential and pleasure, and therefore need to be cast off in the name of "progress" and eating, drinking, and being merry. Such a life is vanity: because of "all these things God will bring thee into judgment," and everything you've done for pleasure, and on youthful impulses, and what was right and progressive in your own eyes will come back to haunt you in the end when you find that your youth merely helped to heap up damnation on yourself. "Therefore, remove sorrow from thy heart, and put away evil from thy flesh..." (Eccl. 11:10a)
Then there are chronological lethargics: those who believe what is good is what has been before and is ripe with age and experience. It has been there and done that, full of wisdom and understanding. Tradition is everything; progress is the enemy, a destructive disease causing decay upon the foundations of civilization. All change is bad; things should stay as they where and are. Such a life is vanity, for old age only means that you are closer to death (Eccl. 12:2-7), when "the dust" and "the spirit" return from whence they came. Your great age serves only to bring you to the end.
As with all of Ecclesiastes, Solomon is not so much calling these "vanities" evil as much as he is saying that they are not THE THING. "Remember now thy Creator..." (Eccl. 12:1a) God is the Lord of the past and future, yes; but in His dealings and relationship with us, He is the Lord of the moment, God of the now. "This is the day the Lord hath made..." THIS DAY: not yesterday, or tomorrow, but today. "His mercies are new every morning..." We are to live in those mercies, not the mercies that have past or the mercies we hope to come. God deals with us on a day to day basis, and He can't very well get through our thick skulls while we're busy being distracted with what could be or was. Young or old, God is to be Reality, not the gone past or the uncertain future. When you are young, remember your Creator NOW (if you suddenly remember Him when you are old, there is not much God can do in your life except take you home). Remember Him in THIS MOMENT, and do that which draws you closer to Him, so when you are old and your spirit returns to God, you will find not a stranger but the One who has walked with you day by day all your life.