Your mind is your best friend, but it is also your worst enemy, involved in self-sabotage. When your mind tells you that you should prepare for tomorrow’s important meeting, it is acting as your friend, causing positive action. When it wakes you up at 3:00 a.m. anxious about the meeting and warning you for the hundredth time about the many consequences of failing, it is acting as your enemy; it is simply exhausting your mental resources without any redeeming value. No friend would do that.
Via Richard Andrews