Bitul Torah--to not learn Torah when one is able is a sin. Not just that, but just like learning Torah is equal to all the mitzvot, so bitul Torah is equal to all the sins. [This is brought own in the Gemara Yerushalmi.] This leaves the idea of Physics and Math ambiguous. [When I was in yeshiva I was unaware of the opinions of the Obligations of the Heart and Saadia Gaon.]
There is a separate issue about secular pseudo wisdoms [the so called soft sciences] which are surely pure bitul Torah because they are false. Even if one can make money by practicing them they are still bitul Torah.
There is a separate issue about secular pseudo wisdoms [the so called soft sciences] which are surely pure bitul Torah because they are false. Even if one can make money by practicing them they are still bitul Torah.
