"When your friends begin to flatter you on how young you look, it's a sure sign you're getting old"

This quote by Mark Twain is a funny way of mentioning the inevitability of aging. It recommends that when your buddies begin to comment on how young you look, it is really an indicator that you are aging. This is since as we age, we become much more familiar with the indicators of aging in ourselves and also in others, and so we are more probable to notice and talk about the signs of youth in our close friends. The quote is a suggestion that aging is a natural part of life which we must welcome it as opposed to trying to eliminate it. It additionally functions as a reminder to value the moments of youth that we have, as they will ultimately pass.