كانت الذرّات، وهي تتحرّك في الفضاء، وحداتٍ منفردة في البداية، ثمّ اصطدم بعضها ببعض لا محالة، فأخذت تتكتّل حيثما سمحت أشكالها بالتشابك. فالماء والهواء والنار والتراب ليست إلا تكتّلاتٍ مختلفةً من ذرّاتٍ ثابتةٍ لا تتغيّر.

“Moving in space, the atoms originally were individual units, but inevitable they began to collide with each other, and in cases where their shapes were such as to permit them to interlock, they began to form clusters. Water, air, fire, and earth, these are simply different clusters of the changeless atoms.”Democritus