Occam ’ s Razor : Simplicity , Complexity , and

HILE COMPLEXITY IS MOVING into every corner of the physical, chemical, and biological sciences, simplicity, elegance, and economy provide the bedrock criteria for choosing among competing hypotheses. Complexity can be viewed as a branch of mathematics. Simplicity can be viewed as a branch of philosophy or aesthetics. Richard Feynman said, “You can recognize truth by its beauty and simplicity. . . . When you get it right, it is obvious that it is right . . . because usually what happens is that more comes out than goes in . . . truth always turns out to be simpler than you thought.” Theories of planetary accretion, mantle dynamics and chemistry, plate tectonics, and crustal growth evolved independently in the last century, and have been patched together to give our current view on how Earth operates. The standard view involves rigid plates, fixed plumes, primordial mantle, and concepts of permanence, uniformitarianism , and steady-state. Paradoxes, inconsistencies, and special pleading in standard views often can be traced back to unnecessary or nonfruitful assumptions. This is where William of Occam comes in.