One of the classic items in the philosopher’s toolbox is the thought experiment. The person conceives of a scenario or a universe, proposes a problem, and engages another person with its implications or meaning. While they may seem simple, thought experiments have rules (or at least guidelines). They should be simple, internally consistent, complete, and conceivable. Martin Cohen, in Wittgenstein’s Beetle, takes the reader through 26 such experiments to help us get a handle on the nature of the universe, the laws of physics, and even the meaning of language.

The book’s 26 experiments are a fun alphabetic tour of philosophy and science—A for Alice’s Acceleration, B for Bernard’s Body-Exchange, and so on. This has the simple effect of keeping our attention on each experiment and not letting them blend together into a hazy mess. He lays out the experiment as originally thought out and invites the reader to a supplementary discussion of each one. Each experiment’s logical implications and revelations are at least mildly interesting. My favorite was at J (for Jules Henri Poincare’s look into alternate geometries):

“Imagine a gaseous world made up of gaseous beings. They exist near the center of the world and as such, expand to occupy a decent amount of space. Surrounding the world is a vacuum whose temperature measures absolute zero but they don’t know it (this is important). One day, they decide to get a fix on exactly how large their planet is, and so begin slowly measuring the distance to the outer edge with a gaseous measuring device (also important). As they slowly make their way to the edge, they get colder and colder, steadily approaching absolute zero, and thereby shrinking along the way (as gases tend to do). Upon getting infinitesimally closer to the edge, they get infinitely small and therefore never reach it. So they give up and go back towards the center (and re-expand to their original size). They relay to the rest of the planet that their world is infinitely large because they never reached the edge.” The implication here is that measurement is relative and based on perception.

While the scenario is wildly fantastic, it still helps inform our understanding of the universe. The other experiments in this book are just as informative. Cohen’s collection is designed to give you nuggets of thought to chew on for a while, then pass along to another one. He incorporates a lot of the original source material (or at least a good translation), but keeps the writing crisp and slightly witty. For those wishing to dip a toe into philosophy, this would as good a place as any to start. A quick and informative book. ( )