>>24983737I don't know if this is exactly right, but my understanding of Fighting-types is that they're supposed to represent a certain spiritual/philosophical aspect towards the perfection of the body, rather than just being big swole dudes.
Fighting-types are martial artists and monks who are in touch with the metaphysical (and thus vulnerable to supernatural attacks), while Normal-types are average joes who are basically protected by their ignorance.
Dark-types are also aware of the supernatural, but openly reject the spiritual/philosophical importance of it. That's why they're known as the 'Evil' type in Japanese, and why they resist Ghost, rather than be immune to it (and consequently why they can attack it back).