Not sure if it is true, but when I first learned about affirmations, you don't even have to believe it. Soon you will but in the beginning you don't. By writing it down instead of just saying it to yourself, triggers one part of the brain. Saying it out loud while humming a simple tune triggers another part of your brain. Saying it while counting also triggers another part of your brain. This is a basic form of "tapping" and by triggering all your brain, soon things begin to change for the best....or whatever it is your are wanting to change.