Testing has its roots in psychology, in the study of the behavior of the human brain. If humans were perfect thinkers, we wouldn't need to test our work. If we were unemotional robots, we would always use testing in a rational way, to reduce risk in our decisions. If we were identical clones, we would all assess risks in the same way. But we are imperfect, irrational, value-driven, diverse human beings. Therefore, we test, and we test our testing.
