The abstract nature of the human psyche doesn't necessarily preclude it from being scientific; rather, it requires innovative research methods and a different set of criteria for scientific rigor.

It's a field that continues to evolve and refine its methodologies, striving to bridge the gap between the empirical and the abstract, and while it may not adhere to the same variables as the physical sciences, it has its place in expanding our knowledge of the human experience.

Modern psychology, as a formal and distinct field of study, is much younger than the other sciences. How can you expect it to rival the others as it's a mere teenager among the wise? It has to mature as a science. Give it time ;)