April 22

The Manifestations of God… affirm that differences [“among human beings and the superiority or inferiority of some individuals to others”] are demonstrably and indisputably innate, and that "We have caused some of you to excel others"[Qur'án 17:22] is a proven and inescapable fact. It is certain that human beings are, by their very nature, different one from the other. Observe a small group of children, born of the same parents, attending the same school, receiving the same education, living on the same diet: some, becoming well educated, will achieve a high degree of advancement; some will reach a middle level; and some will not prove educable at all. It is therefore clear that the disparity among individuals is due to differences of degree which are innate.

But the Manifestations also consider that training and education demonstrably exert a tremendous influence. 
- ‘Abdu’l-Baha  (From a Tablet; The Compilation of Compilations, vol. I, Baha’i Education)