## PHYS208 Fundamentals of Physics II

### Quote of the Day

**The same equations have the same solutions.**

Richard Feynman

Title of Section 12-1 of the book titled "The Feynman Lectures on Physics"

R. P. Feynman, R. B. Leighton, and M. Sands (Addison-Wesley Pub. Co.).

*The first paragraph of that chapter is borrowed here:*

The total amount of information which has been acquired about the physical
world since the beginning of scientific progress is enormous, and it seems almost
impossible that any one person could know a reasonable fraction of it. But it is
actually quite possible for a physicist to retain a broad knowledge of the physical
world rather than to become a specialist in some narrow area. The reasons for
this are threefold: First, there are great principles which apply to all the different
kinds of phenomena -- such as the principles of conservation of energy and of
angular momentum. A thorough understanding of such principles gives an understanding
of a great deal all at once. Second, there is the fact that many complicated
phenomena, such as the behavior of solids under compression, really
basically depend on the electrical and quantum-mechanical forces, so that if one
understands the fundamental laws of electricity and quantum mechanics, there is
at least some possibility of understanding many of the phenomena that occur
in complex situations. Finally, there is a most remarkable coincidence:
*The equations for many different physical situations have exactly the same appearance.*
Of course, the symbols may be different -- one letter is substituted for another --
but the mathematical form of the equations is the same. This means that having
studied one subject, we immediately have a great deal of direct and precise
knowledge about the solutions of the equations of another.

"http://www.physics.udel.edu/~watson/phys208/quote11.html"

Last updated Nov. 5, 1997.

Copyright of the Feynman Lectures belongs to the California Institute of Technology, 1964.