“Success is not final, failure is not fatal: it is the courage to continue that counts.” — Winston Churchill
“You have power over your mind, not outside events. Realize this, and you will find strength.” — Marcus Aurelius · Meditations
“Your limitation—it's only your imagination. Push beyond limits.” — Unknown · commonly attributed to various sources
“The future belongs to those who believe in the beauty of their dreams.” — Eleanor Roosevelt · widely attributed