Atoms

"At sea level, at a temperature of 32 degrees Fahrenheit, one cubic centimeter of air (that is, a space about the size of a sugar cube) will contain 45 billion billion molecules. And they are in every single cubic centimeter you see around you. Think about how many cubic centimeters there are in the world outside your window - how many sugar cubes it would take to fill that view. Then think about how many it would take to build a universe. Atoms, in short, are very abundant.

"They are also fantastically durable. Because they are so long lived, atoms really get around. Every atom you possess has almost certainly passed through several stars and been part of millions of organisms on its way to becoming you. We are each so atomically numerous and so vigorously recycled at death that a significant number of our atoms - up to a billion for each of us, it has been suggested - probably once belonged to Shakespeare. A billion more came from Buddha and Genghis Khan and Beethoven, and any other historical figure you care to name.

"So we are all reincarnations - though short-lived ones. When we die our atoms will disassemble and move off to find new uses elsewhere - as part of a leaf or other human being or drop of dew. Atoms, however, go on practically forever. Nobody actually knows how long an atom can survive, but according to Martin Rees it is probably about 10^35 years - a number so big that even I am happy to express it in notation."

Bill Bryson, A Short History of Nearly Everything, p. 133-134