Wrong thinking, whatever its nature, leaves indelible scars on mind and body alike. It affects character and material prospects equally. Every time you grumble or find fault; every time you lose your temper; every time you do a mean, contemptible thing, you suffer a loss which cannot be repaired. You lose a certain amount of power, of self-respect, and of an uplifting and upbuilding character-force. You are conscious of your loss, too, which tends to weaken you still further.
A business man will find that, every time he gets out of sorts, flies into a rage, or "goes all to pieces" when things go wrong, he is not only seriously injuring his health, but is also crippling his business. He is making himself repellent; he is driving away success.
A man who wants to do his best must keep himself in good mental trim. If he would achieve the highest success he must be a correct thinker. He cannot think discord and bring harmonious conditions into his business. His wrong thought will honeycomb and undermine his prospects of life.