Age defined perfectly :
Youth is when you smoke, drink, and are naughty all through the night, and the next morning you still look like you haven't been doing any of that.
Middle age is when you smoke, drink, and are naughty all through the night, and on the next morning, you look like you have been smoking, drinking and have been naughty all through the night.
Old age is when at night you neither smoke nor drink, nor are naughty, yet on the next morning you look like you have been smoking, drinking and have been naughty all through the night.
Youth is when you smoke, drink, and are naughty all through the night, and the next morning you still look like you haven't been doing any of that.
Middle age is when you smoke, drink, and are naughty all through the night, and on the next morning, you look like you have been smoking, drinking and have been naughty all through the night.
Old age is when at night you neither smoke nor drink, nor are naughty, yet on the next morning you look like you have been smoking, drinking and have been naughty all through the night.