ABSTRACT
Physical reductionists understand matter to be made of a hierarchical arrangement of increasingly small components, ending—perhaps—at some fundamental microscopic level. The reductionist vision is the framework that has successfully and usefully guided the arrow of scientific discovery since antiquity. Physical reductionism, in particular, is a powerful, intuitive idea and arguably a simple matter of common sense. The Roman natural philosopher Lucretius advanced his own reductionist atomic model in the first-century BCE, envisioning all matter constructed of fundamental “bodies” separated by voids. Democritus was a fifth-century BCE philosopher, also from Abdera. The ancient Greek natural philosophers would have raised an obvious objection that real things should at least occupy some space. Philosopher John Heil has made a helpful distinction between the “substantial parts” and “spatial parts” of an object. “Substances,” Heil writes, referring essentially to elementary building blocks of nature, “are not hidden beneath, or masked by, their properties.
