Gaps In Our Knowledge

I was working with Sam the other night to prepare for his science test (8th grade) that covered atomic structure and basic elements.  While the concept of protons, electrons and neutrons was relatively easy to explain, the question as to by multiple protons did not repel each other, thankfully did not come up.  After all, this is 8th grade science.  But later on, I did find it curious how there was a half-page section at the end of the chapter to cover the four fundamental forces of nature.  Although he was not required to learn about the strong and weak forces, I had to explain to him how it worked.  And this is when I found myself trying to find non-mathematical constructs that I can state to a 13-year old in terms he could relate to.  After a while, I just could not find a simple explanation other than how I've really felt about the strong and weak forces.  Gravity and electromagnetism is intuitive and macro but those are other two, I said, were more mathematical abstractions to fill in the gap in man's knowledge of the physical universe.  Somewhat, faith-based, not in a traditional religious sence.  But in this case, physicists' faith that the language of mathematics can provide some kind of rationalization of why things are the way they are.  It's messy and non-elegant and it makes a lot of people, including myself, uneasy.  The theory that unifies the four forces of nature had eluded physicists for a while now and I'm not sure I'll see it explained in my lifetime.  But that's the beauty of science, I went on to explain.  If some smart guy (or gal) comes up with a better explanation of why protons don't repel each other within the nucleus of an atom, the scientific community will gladly throw away old theories and re-write textbooks.  If there was anything Sam learned in that chapter, I hope it was mainly from our little side discussion of the scientific process.