We have the psychology tag right now. However, it mostly seems to be a placeholder tag for questions that the asker wasn't sure how to tag. I don't really understand why we would need this tag, since we have a specialized tag for every subfield of psychology: cognitive-psychology, developmental-psychology, abnormal-psychology, social-psychology, etc.
I don't think it is a good idea to keep a very vague and 'can-apply-to-almost-any-question-on-the-site' tag around, especially when we have so many more focuses, but still easy to use tags. What do you think?