All of what you mention are Nerf sciences. Hard sciences are physics, computer science, etc.
What's so hard about those? Lifting those heavy pencils?
Now digging square holes in the hot sun, that's hard science!
Nah, it's just the thinking. Most scientists don't suffer under that burden.
I do have a theory, though. That the intelligence of the scientist is inversely proportional to the intelligence of the research subject. So you have the following partial ranking: