The intelligence of an individual in not a fixed quantity.

Comprehension, inventiveness, direction, and criticism: intelligence is contained in these four words.

Heredity, to our understanding is not capable of giving to this illness (paraphilia) its characteristic form ... Heredity invents nothing, creates nothing anew; it has no imagination.

Our purpose is to be able to measure the intellectual capacity of a child who is brought to us in order to know whether he is normal or retarded. ... We do not attempt to establish or prepare a prognosis and we leave unanswered the question of whether this retardation is curable, or even improveable. We shall limit ourselves to ascertaining the truth in regard to his present mental state.

The intelligence of an individual in not a fixed quantity.

Could we look into the head of a Chess player, we should see there a whole world of feelings, images, ideas, emotion and passion

Some recent philosophers seem to have given their moral approval to these deplorable verdicts that affirm that the intelligence of an individual is a fixed quantity, a quantity that cannot be augmented. We must protest and react against this brutal pessimism; we will try to demonstrate that it is founded on nothing.