Chemistry is defined as the study of matter and its properties. With regard to this definition, the roots of the study of chemistry can be traced back to more than one ancient civilization. Most notably, the Greeks and Chinese each independently postulated thousands of years ago that there must be a small number of elemental substances from which all other things were created as admixtures. Remarkably, both civilizations theorized that air, earth, water, and fire were among those elements. It was much more recently, however—just about 300 years ago—that famed French nobleman and chemist Antoine Lavoisier correctly identified one of the elements experimentally. Lavoisier’s discovery is often cited as the event that heralded the birth of chemistry as a proper science. Theorizing based on observation of natural systems began to give way to controlled testing of the properties of matter, leading to an explosion of understanding, the echoes of which are still ringing in modern-day laboratories.