[wahern]

What we today call science was once called natural philosophy. Philosophy was simply the systematic study of the world, including physics, logic, and math, as opposed to theology or learning an applied professional trade such as medicine, law, or architecture.

The terms we use to differentiate fields of study are still shifting. Nobody uses the term "naturalist" anymore, at least not to refer to a scholarly field. There's often a huge overlap between math and various other fields. I'm not sure the recent explosion in degree names is any better than using Ph.D. It's tempting to suggest that fields like Art History and English Literature should be differentiated from [modern] Physics, but ideally scholars in all those fields should be (and often are) using many of the same analytical techniques. And realistically, I doubt usage of a shared signifier, Ph.D, is causing any consequential confusion. Arguably, as specialization increases the value of using Ph.D increases--it general implies someone has attained the highest credential in their field of study, whatever the field.