Intellectual Independence, and the traits and abilities it fosters, are the hallmarks of what physics has to offer as part of a culture. We can simply compare those to what we experience today, to see which things remain undone.
The first thing, we noticed already, is that we tend to hear about Physics too passively, too much as if it were a canon. That so contradicts even the way the words are defined, that if we understood physics we should find it unnatural and uncomforatble to take that way. It should feel strange like always hearing, and not understanding, directions intended for someone else would feel strange, when one knows that directions can have so much more personal value than that.
When we experience dimensional analysis for the first time, it will begin to become apparent that an immense range of questions can be answered almost effortlessly, from remarkably simple rules. No other single topic will give us so much power for so little structure, but all the other topics of modern physics contribute the same kind of new ability, in one way or another. With hindsight, we will see how little of this knowledge is ever used outside of the very narrowest communities of professional physicists. Yet the questions it could answer for us, questions of scale and beyond, are precisely the questions that occur every day, in simple practical problems.
Moreover, physical law has made it possible to see a remarkable degree of coherence in the events of nature. The coherence has always been part of the events, but the ability to recognize it adds a whole new aspect to nature's wonder.
Finally, in our relations with each other, we suffer from rather bad intellectual dependence, and hence a number of different library problems. It is probably best not to belabor these, and instead to let the reader notice them for himself, after having experienced a few times the confidence of knowing you are right, in an answer that you provided for yourself, and that you know you could re-create if circumstances changed.
In this last area, we are particularly lucky that Modern Physics is the subject matter of this book. It is the right subject matter to discuss for the same reasons that language and dimensional analysis are the right topics to discuss. Modern Physics is special for the way it lays an order and a simplicity over everything currently understood.
At the same time, precisely because they have not penetrated the culture, the topics of modern physics are still unfamiliar and somewhat exotic. For one thing, this makes them fascinating to experience for the first time. For another, though, they make an ideal context in which to display ``how physics works''. The questions we will ask will reach far beyond anything that is commonly known, even with the help of the most respected authority. They also span such a range that one would have to spend a long time in deep libraries to find answers to them pre-stated. Yet the questions we will ask, and the answers we will find, will be completely managable within the domain of one individual's mind.