I don't see why not. There's so much literature (check out the self-help, positive psychology, self-improvement, etc at a bookstore/library) banking on the theory of its effectiveness.
Let's begin with our own thoughts. You know, the conversation you have with yourself (we all have these and no you're not abnormal because of it). For the most part, we all have our own perception, opinions and thoughts of our self. *Think self esteem.
Now, if a fly were to hang out in the walls of your mind and thoughts...what would it hear? Are those conversations with yourself; positive/neutral/negative?
I recall a patient tell me he thought the very worst of himself the second he woke up...every day. How do you think the rest of his days played out? Not great.
From that meeting, we began experimenting with his first thoughts to himself. For him, he felt it was silly, pointless and perhaps a juvenile recommendation from his therapist. But alas, he began detangling his negative self-talk and replacing it with either neutral and later positive self-talk. I literally "prescribed" him to come up with daily affirmations. Guess what? Over some time, that initial thought of thinking he was "useless" and "lacking a purpose in life" first thing in the morning happened less and he began feeling better about himself!
Some people write quotes/affirmations on post its, have it tattooed, and others (like myself) like to receive it via text (Shine text!) and via my social media feed.
If you enjoy daily motivation, positive quotes, inspirational photos...TIY will be posting Daily Motivation during the week via Instagram. Follow my IG page @trueimage_yoga and get in on the fun. Who said there's such thing as too much inspiration?