To some degree, I'd say probably.
A lot depends on drive and teaching materials.
When a company I worked for was having problems with some of their products, I went out and found a book called 'Problem Solvers: Chemistry'. I was able to learn some basics and how to use mathematical formulas used in chemistry.
As a result, I solved many of those product problems.
The Chief Engineer asked the president of the company if I could be transferred into engineering.
He said no, because I didn't have a degree.
It was the will to learn and solve problems that worked.
I think anyone with average intelligence and drive could have done the same.
But can most everyone teach themselves to be a talented physicist? I'd say no.
Most of us need the guidance of a good teacher.
Posted 283 day(s) ago