Whatever your heart dwells on is a part of your mental and physical composition.
You cannot separate your thought from your outward appearance.
Thoughts are the inner yearnings of a man for something he wishes to have or is planning to have. It is the structure that tends a man towards or away from his goals.
Insanity and sanity is enhanced through the process as produced by a man's thought. As you think it in your heart, so are you.
A man who wants to win will not dwell on negative thoughts, he will ensure his mind constantly flows with positive and productive numbers.
Never think for once that what your thoughts dwell on does not matter, you are every bit your thought and you cannot do something different from what your mind is programmed to do.
Be happy and make your thoughts inspire an outward appearance that will indeed make the process of thinking worth it.