All Science Subjects: How Much Can You Learn?

[PhysicsKid0123]

How hard is it to know almost every area of science? I am majoring in physics and want to pursue a PhD in physics, but I also want to learn a lot of the other subjects like math, chemistry, computer science, and engineering. If I could I would pursue PhD in all these fields but that probably is not possible. I don't necessarily want to get degrees in these fields but how much knowledge will I be able to gain from these fields if taught my self and read texts books on this?

 

[danago]

I haven't done a PhD myself, but I imagine it would be tough enough to stay at the cutting edge of your own field, let alone at the cutting edge of every other field. But if you want to just have an above average understanding (whatever that means) then I think it wouldn't be too hard. I guess what I am getting at is that it really depends on how exactly you define "knowing" an area of science.

 

[jtbell]

I think anybody who's studied for a Ph.D. will tell you that as you proceed further and further, the more you realize there is to know, and the more narrowly focused your knowledge becomes. There are only a certain number of hours in a day, and you end up spending most of them just gaining enough knowledge to write a dissertation on your specific topic.

You may pick up other stuff along the way, if only from chatting with colleagues about their projects and attending departmental colliquia, but it will be a superficial sort of knowledge, and more so the further it gets from your own topic.

And that's just in one field, e.g. physics. Forget about chemistry, math, etc., except maybe at the introductory undergraduate or "intelligent layman" level.

 

[Ryan_m_b]

I think anybody who's studied for a Ph.D. will tell you that as you proceed further and further, the more you realize there is to know, and the more narrowly focused your knowledge becomes.

Reminds me of this illustration: http://gizmodo.com/5613794/what-is-exactly-a-doctorate

It's not really feasible to get more than one PhD and stay current in a field. Regardless a PhD doesn't make you an expert in a field, it makes you an expert in a very, very, very specialised section of that field.

You could spend a lot of time studying other subjects and become fairly knowledgeable on it but consider the fact that even full time at university you only learn a slither of what there is to know about your subject. During my undergrad I did eight terms each with four modules (with the final devoted to a research project IIRC). The first three terms had three mandatory modules and one which could be chosen out of a group of four. The next three terms had two mandatory, two options out of eight and the last two terms had no mandatory and four options out of sixteen.

Hence to get a "full" biology undergraduate degree in which I didn't specialise and studied all 83 modules (rather than the 24 I did do) would have taken me ~7 years. And by then I probably would be very out of date with what I started, let alone the prospects of learning outside of my field.

It's entirely possible to gain a conceptual or even beginner understanding of another field but there's just far too much to learn for one individual to ever be an expert in one entire field, let alone two.

 

[Choppy]

Have you heard the one about the grad student whose knowledge advanced steadily in an ever narrowing scope of his field?

He learned more and more about less and less until he knew absolutely everything about nothing.

Of course you can't learn everything. You learn the basics and build on them and if you pursue a PhD you develop an extremely specialized base of knowledge. You can expand on that after the degree. You can learn things as you need them and it's generally not necessary (or wise) to do another PhD to accomplish that. As others have pointed out, there's only a finite amount of time in the day and that means that developing the kind of specialized knowledge you get from a PhD in another field will require a certain sacrifice at staying current in the one you're already in.

One popular solution to this is called collaboration.