Most confusion, in the study of ourselves, happens when we stop studying ourselves the way we would study other things. But this is not easy to do. I'd like to offer the key to this disentanglement. First let me describe the problem.
When studying the world, we try as hard as we possibly can to get out of our skins. This is the essence of science: we are studying nature, the world outside ourselves, not just 'forming opinions'. So we need to cast aside assumptions, stipulations, declarations, dogmas, a priori truths, and as much interference by our own instinct and experience as we can identify. We need to instead find explanatory theories, consider what an explanatory theory may be, test the theories, find relevant evidence, improve the theories, etc.
We struggle with this. We don't know what will come up about us as we work. We are "in the way", when we study nature. Is gravity "explained" by the theories of Newton and Einstein, with their assumption of a strange, pervasive force whose effect we can see and feel, but whose nature either eludes us or doesn't satisfy us?
When studying ourselves, these problems are compounded immensely.
The method of science, described above, for example, has mistakenly been used, on-and-off for centuries, as a description of essential parts of human nature. In science we try to get rid of the a priori, the assumptions before our experiments, but, unfortunately, humans, like other living things, have built-in a priori structure: our genetic endowment. Genetic information clearly provides the hidden structure of our brain, which allows, shapes and captures our experiences. Without those structures in our brain, whatever they are, we wouldn't have human experience. A cat without its brain wouldn't have cat experiences, in exactly the same way.
So in the science of studying ourselves, a priori stipulations about ourselves are bad, but we are trying to discover the a priori structure (launched by our genetics) that literally makes us human. This has been the source of phenomenal confusion in the study of man. People will use their intuition to try to understand the nature of the universe, but really, their gut is usually telling them something about the nature of living things, humans nature in particular, not necessarily (without further study) about anything outside of themselves. Conversely, scientists will demand proof and avoid assumptions and therefore think that humans by their nature are somehow "blank slates" that assume nothing and demand proof. Which is itself an assumption, an anti-scientific one, in fact, because it flies in the face of our understanding of our biology, where genetics clearly sets the scene for humans to live their lives.