That was Ralph Kramden in the Honeymooners quoting George Bernard Shaw.

Here's how you know you're no longer young (which isn't a bad thing):

When you are asked the question, "Would you rather experience any 5 days of your choice in the future, or relive any 5 days of your choice from your past?", the moment you select the latter is when you officially are no longer young.

I would much prefer to relive days from the past.