University of Waterloo psychologists tested this exact practice in 2009. They had people with low self-esteem repeat “I am a lovable person” each day. Those participants felt measurably worse afterward than a control group who said nothing. The affirmation revealed the gap between the statement and their actual self-image, making that distance feel larger rather than smaller.
The explanation comes from what psychologist William Swann at the University of Texas called self-verification theory. Your brain checks every self-statement against your stored self-image. If that image says “I am not particularly likable,” and you tell it “I have a great personality,” the brain treats the new statement as a threat and pushes back. The gap triggers rejection, pushing the stored image deeper rather than lifting it.
For people whose self-image is already neutral or positive, though, the same words behave completely differently. Researchers at Carnegie Mellon used fMRI brain scans in 2020 to map the exact pathway. Affirming a personal value lit up the ventromedial prefrontal cortex (a reward region just behind your forehead), and that activation then dampened the brain area that registers threat.
UCLA researchers measured cortisol separately in 2005. People who spent two minutes affirming their values before a stressful task came out with significantly lower cortisol than the control group. Cortisol is your primary stress hormone, so the body’s stress response had measurably changed.
Your inner monologue is also running this loop constantly. Ethan Kross at the University of Michigan points to research showing inner self-talk runs at roughly 4,000 words per minute, about 30 times faster than spoken speech. Most of that stream is about who you are, and for most people, those statements run without any conscious selection.
Two modifications improve the success rate of the monk’s method. Saying “You can do this” in the second person outperforms “I can do this” across multiple Kross studies, because the slight distance sidesteps the brain’s consistency check. And replacing trait statements like “I am a hard worker” with values statements like “I care about hard work” bypasses the brain’s fact-checker entirely, because a value is harder to dispute than a claimed trait. The science says the words matter less than the gap between what you’re saying and what you already believe about yourself.