Each generation has its few great mathematicians, and mathematics would not even notice the absence of the others. They are useful as teachers, and their research harms no one, but it is of no importance at all. A mathematician is great or he is nothing.
Alfred AdlerWhat do you first do when you learn to swim? You make mistakes, do you not? And what happens? You make other mistakes, and when you have made all the mistakes you possibly can without drowning - and some of them many times over - what do you find? That you can swim? Well - life is just the same as learning to swim! Do not be afraid of making mistakes, for there is no other way of learning how to live!
Alfred AdlerFar more unwaveringly, the neurotic keeps before his eye his God, his idol, his ideal of personality and clings to his guiding principle, losing sight in the meanwhile of reality, whereas the normal person is always ready to dispense with this crutch, this aid, and reckon unhampered with reality.
Alfred Adler