Chapter One: Pre-1895: The Dawn of Time
To run any race you must know the course. To build a time machine you need to know what time is, just as you cannot fly without knowing the nature of air and aerodynamics. But understanding time is easier said than done.
A celebrated Zen riddle asks, when a tree falls in the forest and nobody is around, does it make a sound? This riddle can probably be applied to time. Would there be such a thing as minutes or years if no human beings could experience their passage?
This seems to be a very odd suggestion, but the nature of time is very strange. Indeed, it is a real puzzle for science....