In the seventh century BC, Thales said that the arche of everything was water. Since then, ancient Greek philosophers began seriously and extensively to explore the concept of arche. Later, Aristotle accepted the four-element theory proposed by Empedocles and established a completely theoretical system to sketch out an image of cosmos. Today, through exploring the image of cosmos built by classical four-element theory, we can not only understand the contributions of ancient Greek philosophers, but also inspire our wisdom.