visualized such problems, placing his "brain" into his diagrams like Alice plunging
through the Looking-Glass. He tried to make his students imagine the apparent width
and depth of an object:
They depend upon how we look at it; when we move to a new position, our brain
immediately recalculates the width and the depth. But our brain does not immediately
recalculate coordinates and time when we move at high speed, because we have had
no effective experience of going nearly as fast as light to appreciate the fact that
time and space are also of the same nature.
The students were sometimes terrified.
That is the same with all our other laws---they are not exact. There is always an edge of
mystery, always a place where we have some fiddling around to do yet. This may or may not be a
property of Nature, but it certainly is common to all the laws as we know them today.
Nature uses only the longest threads to weave her pattern, so each small piece of the fabric
reveals the organization of the entire tapestry.
Meanwhile, why does an object in motion tend to travel forever in a straight line? That, Feynman
said, nobody knows. At some deep stage, the explanations must end.
A theorist who can juggle different theories in his mind has a creative advantage, Feynman argued, when it comes time to change the theories.
Different theories tended to give a physicist "different ideas for guessing," Feynman said.