Psychology is still evolving. The 1960s so the dawn if Systematic Desensitization. Later, there was the development of Cognitive Behavior Therapy, then Dialectical Behavior Therapy, and not Acceptance and Commitment Therapy. Some forms of knowledge take longer to develop than technical advancements. The same can be seen in development. Science, mathematics, and musical ability develop early in the development of children, but genius in social science is usually not evident until adulthood. The reason for this is believe to be that the social sciences require an accumulation of knowledge and associations, while the more scientifica , mathematical, and musical advancement require insight into knowledge that is instantly observable, basically the difference between simultaneous insignt and sequential insight.