Physics is the science that forms the foundations for the other sciences and for much of engineering. It is based largely on mathematics– more so than most other sciences. It therefore has a reputation for being difficult. This is apparently at odds with the most thoughtful definition: Physics is that science which considers the simplest systems and then tries to achieve a complete description of them. It is the aim for completeness that causes the difficulty. A biologist cannot hope to produce a complete description of even a single cell. It should be evident that physicists are adept at looking for simplifications. If none appears without oversimplification, then the problem is generally turned over to a different science.
Physicists have considerable self-awareness of their participation in their science. They have undergone a training that emphasizes the unity of the field, in spite of the...