I actually often see the opposite less intelligent people are often carefree and more happy.
Quotes are like bible passages. There is one for every occasion and every perspective. Given one quote, you can find an equally poignant and contradictory quote.
Time and tide wait for no man!
Slow and steady wins the race!
This is why I cringe when I see people leading their lives based on quotes.
A witty saying proves nothing -Voltaire