Democritus (ca. 460 BCE to ca. 370 BCE) was among the earliest Greek philosophers to propose this scenario: if you divide something into smaller and smaller parts, and keep dividing them, eventually you would end up with their “base” material, an inseparable unit of matter. What, exactly, is this base material? Democritus gave this hypothetical substance a name: atomos (or, in English, atoms). Literally translated, it means uncut or indivisible.
In 1897, British physicist J.J. Thomson made a remarkable discovery. When he shot cathode rays through an electric field he noted that they were deflected, leading him to posit that the rays themselves also had a negatively charged sub particle. It turned out the atom was divisible after all: it had electrons.
In 1909, Ernest Rutherford, another British physicist, oversaw an experiment at the University of Manchester. By firing alpha particles at a thin sheet of gold foil, he and his team discovered that some particles, but not all, would scatter in unpredictable directions. This is regarded as the discovery of the nucleus. Atoms not only had negative electrons, they also had a dense, positively-charged core.
These are only but a few of the discoveries along the way that have led us to a remarkable view of the world: matter, seemingly constant, is in constant change. We ourselves are compositions in continual transformation. Marveling at this reality, philosopher, historian, and poet George Santayana wrote,
…all we observe about us, and ourselves also, may be so many passing forms of a permanent substance. This substance, while remaining the same in quantity and in inward quality, is constantly redistributed; in its redistribution it forms those aggregates which we call things, and which we find constantly disappearing and reappearing. All things are dust, and to dust they return; a dust, however, eternally fertile, and destined to fall perpetually into new, and doubtless beautiful, forms. This notion of substance lends a much greater unity to the outspread world; it persuades us that all things pass into one another, and have a common ground from which they spring successively, and to which they return. (Santayana, 1910)
It is mind numbing to wrap our heads around, but you and I and all the objects we see, touch, and feel today were once other things. Millions of ‘other things.’ Contemplating life at the atomic level has kept many philosophers and poets up late into the night. It provides a tireless supply of metaphors to celebrate our interconnectedness and synergistic connection to one another, and every thing. So even if you haven’t looked at a periodic table since you were in school, and even though you will likely not spend any other time contemplating molecular structures today, start your day here, at the atomic level of reflection. Everything around you is permanence in an impermanent state — including you.
What are you made of? Exactly the same stuff as everyone else.