it's a correlation not a causation. "smart people" (actually just over achievers like those who excel at aptitude tests or collect diplomas) tend to be overly contemplative. Dwelling on things rarely resolves them, and usually just leads to angst.

If your contemplating leads to resolving the issue in the near term -- by all means carry on.

But for most people, their brooding over their relationships, family history, achievements etc only leads to misery.

Focus your efforts outside of yourself.