> There are sociological reasons why students of science are not encouraged to read Newton for themselves.
Like what? Do you think physics teachers are afraid their students will find out Newton believed in God and then they won't be atheists? Do you think they're pushing materialism or "scientism" and rewriting history to that end? This is close to a conspiracy theory. I think you're ascribing malice or ill intent to what are almost purely pragmatic choices.
Here's the text of The Principia[1], read a few pages and imagine a physics student trying to make sense of it. When I finally opened it I found exactly what I had always been told I would find: something interesting but hard to read and not the best place to learn physics. I don't think there are any physics books today that prove the fundamentals of calculus in the middle of their discussion of physics. That's a pedagogical nightmare. Today you learn calculus and then you do physics with it, but Newton developed calculus to do physics so there were no calculus books he could assume his audience was already familiar with.
[0] - https://en.wikipedia.org/wiki/General_Scholium [1] - http://www.archive.org/stream/newtonspmathema00newtrich/newt...