Occam’s razor is to not multiply causes unnecessarily by preferring the simpler theory. A century ago, Bertrand Russell argued that life isn’t virtual by appealing to common sense and Occam’s razor:
“There is no logical impossibility in the supposition that the whole of life is a dream, in which we ourselves create all the objects that come before us. But although this is not logically impossible, there is no reason whatever to suppose that it is true; and it is, in fact, a less simple hypothesis, viewed as a means of accounting for the facts of our own life, than the common-sense hypothesis that there really are objects independent of us, whose action on us causes our sensations.” (Russell, 1912).
Does the same argument still apply today? It is still common sense that there is a reality out there apart from us, but that our entire universe once existed at a point isn’t common-sense at all. Today, common-sense is just as likely to accept that our universe booted up from a small beginning.
The direction of Occam’s razor has also changed. In Russell’s time, physics was based on a few particles, each with mass, charge, and spin, but now it needs forty-eight particles, that have twenty-four properties, plus five invisible fields, that generate fourteen virtual bosons, just to explain the basics. To explain inflation, neutrinos, or dark matter, needs even more fields, particles, and bosons. And our best universal theory, string theory, needs eleven dimensions to work at all.
It’s hard to imagine anything more complex than physics today so if it is preferred, it isn’t because of its simplicity! In contrast, the following chapters explain the same facts using one quantum process, one extra dimension, and one quantum field. Last century, physical realism may have been the simpler theory, but not today. Fast forward a hundred years and quantum realism is far simpler than physical realism, so now Occam’s razor cuts the other way.