Basically, what this book is about, as the title implies, is a study of what it is to be a body, with all the characteristics bodies have as such.
It is not quite so simple, of course. Since what today are called the "physical sciences" study bodies, and since especially physics and chemistry make as their study bodies in what might be called their "bodiliness" (as opposed to biology, which studies bodies as living), we are going to have to do several things to make this study worth while.
In the first place, we will have to justify what we are doing as scientific, if it is different from physics and chemistry, and they are sciences. Secondly, we will have to show that it is different from physics and chemistry, and not only something that neither of these sciences treat, but something that they cannot treat. Thirdly, we will have to relate our conclusions to those of physics and chemistry, and show how what we have discovered supplements what is known from physics and chemistry.
Since there is a (somewhat justified, given the historical situation) prejudice against philosophy as scientific, the first task we face is to investigate what science is doing, and why it manages to advance. Hence, the first part of the book is not going to be about bodies at all, but about scientific method: what it is, why it works, why it apparently deals only with what is observable, but actually goes beyond observations, and why it is justified in doing so.
We are not going to do a historical survey of what is called "philosophy of science," which has, in this century, undergone several drastic changes, because of problems which, I think, stem from its taking the Kantian notion of "cause" as "the" notion of cause and rejecting it, and thus trying to explain science without resorting to causes. I contend that this is bound not to succeed, because science deals precisely with effects and causes--though not in the Kantian sense of the term. "Effect" and "cause" must be carefully defined. Once this is done, a coherent theory of why scientific method works can be developed. What we are going to do is try to develop this theory, and only refer in passing to other theories which differ from it.
At any rate, what we are first going to do is try to make out a case that a proper definition of "effect" and "cause" can make sense out of what scientists are doing; and then generalize the scientific method so that we can do philosophy with a version of it, and have some hope that what we are doing will be scientific and not mere speculation.
In this first part, then, we will discuss the starting-point of scientific investigation, and the five traditional "steps" of scientific method: observation, hypothesis, experiment, theory, and verification. We will see why science uses operational definitions, why scientists tend to measure things, and why mathematics, especially probability and statistics work as scientific tools, why theories are supposed to be simple, logical, and comprehensive, why they almost universally predict something, why models are useful in theories, and why "verification" is really "falsification." This theory of science will then predict that a science like philosophy ought to exist if it is true; and we will show that the prediction is verified and develop our philosophical method.
We will then be able to enter into our philosophical investigation of bodies; and I am going to divide up the investigation into two parts, taking my cue from physics; the first will be what I call "philosophical statics," the second, "philosophical dynamics."
Philosophical statics describes the constitution of a body as such ignoring changes which may happen to it; if you will, it will be a description of what changes, rather than what it is doing as changing. In this section, we will try to see what energy is, and show why the philosophical definition of energy is what is being referred to by the different definition in physics. We will try to show what it is about energy that allows it to be measured, what its relation is to force and work, and why mass is to be considered a form of energy. We will look at those strange forms of energy called fields, and see how they account for what we think of as distance, position, and space; and while we are about this, we will be able to solve a problem that has been plaguing physicists for the past thirty years or so.
In the second part of philosophical statics, we will try to describe, not single forms of energy, but units of many forms of energy. This will allow us to see what "matter" is, and what bodies actually are; and while we are about this, we will see a basis for the conservation of matter, and why it is the conservation of mass-energy.
In entering philosophical dynamics, we will first discuss what is involved in any change, and the bodily conditions that make change possible. We will then be able to define the two basic kinds of change (those dealt with in physics and chemistry), and show what the conservation of energy has to do with changes in bodies. Then we will concentrate on the act of changing itself, and consider process and especially movement, showing how Newton's laws apply. We will see that every process has a purpose, and how process is related to direction and velocity, as well as why velocity is a "vector quantity" rather than a "scalar." Process, we will discover, has two quantities, length-of-process and velocity; and it is the relation of these two which is the basis for time.
Once time is introduced, we may discuss the relativity of time, and try to arrive at some notion of momentum and acceleration. This will lead us deep into problems connected with Einstein's General Theory of Relativity and quantum mechanics. Our own approach will allow us to make a prediction that it might be possible, by taking an entirely different focus on physical bodies (the one implied by this philosophical theory) to develop a physics that combines classical, relativistic, and quantum physics into a consistent single approach.
We will finish philosophical dynamics by making another prediction, about the nature of evolution.