Physis is the origin of our word physical, physiology and physics.

Physis was the Greek word for the material universe we sense, experience, examine and measure in an attempt to predict future behavior.

This view of tree rings suggests that the past geological record is still observble in the world we see today. Thus the quest to understand, predict, measure and examine nature involves observation and prehistorical details of the geological record. This focus on the material and the temporal is the basis of scientific inquiry today.

In Ionia, a Greek province, these thinkers who examined physical reality were referred to by Plato and Aristote as: physikoi, the natural philosophers or philosophers of nature. Among them was Thales who conceived of the primordial origin of the cosmic regularity sensed by us was the primary element of water. He believed the universe emerged from a primordial aqueous solution like an embryo in an egg's allantoin, or fluid membrane.

Greek physical thought produced variations on ideas about creation and the origins of all material existence. Among the ideas discussed by the physikoi was the four elements that combine to form the sensory reality of the material world. By the time of Aristotle these ideas coalesced into the doctrine of the four elements.

These charateristics and elements were the constituent parts of all material things in creation.

A related but very different conception of matter was held by Chinese material philosphers.

This use of reasonable gategories to make sense of the physical conditions of existence is the mainspring of science.

Our motivation to love the world requires that we explain what that physical and metaphysical world means to us. Our affection for nature has been referred to as an erotics of place.

Physics, physician, and physiology all stem from this same root word. By the time of Heraclitus (BCE 234) this word Physis, was the equivalent of our idea of nature. Nature here referred to the indestructable, elemental, immortal totality of the cosmos -- which Plato said was a living being. In the Greek debate as to the exact meaning of physis is a revealing paradox in our relationship to our surroundings.

Some argued that nature referred to the organizational patterns inherent in all things. Others empasized a fluid process of fluctuation. Hercalitus and Democritus argued that nature referred to either the "structure of things or the development of things."

What then accounts for the order of things, the importance of physical knowledge in relation to the other ideas we cobble together as we design our worldview.

Three distinct -- yet related and tightly connected, meanings emerged from the early arguments of the philosophers from the time of Thales to the death of Ptolemy.

1. Foremost was the idea of growth and the process referred to a genesis or the origins of life.
2. It also referred to the primordial material, arche, in Greek, out of which the perceivable universe is crafted.
3. The word referred to the internal principle of organization that makes things function according to a process.

This is the task of the physical sciences, to reveal the order, periodicity, form, function, structural dynamics and inherent meaning of actual material existence.

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