Is the earth alive? That depends on the criteria you use to determine life. Certainly not if you include criteria such as the ability to reproduce. But respond to stimuli? Respire? Those criteria are a little more difficult to determine. Certainly the earth is alive in a way that no other planet in our solar system is alive. And certainly it supports life as perhaps no other planet in the universe can. And that we owe to what happens not on the earth, but under it.

I will leave it to Ward and Brownlee, authors of Rare Earth to whom I owe this understanding of the process involved, to explain more clearly: “The final composition of the earth had several crucial structural effects. First enough metal was present in the early Earth to allow formation of an iron and nickel rich innermost region or core that is partially liquid. This enables the Earth to maintain a magnetic field, an invaluable property of a life-sustaining planet. Secondly there were enough radioactive metals, such as uranium, to make for a long period of radioactive heating of the inner regions of the planet. This endowed Earth with a long-lived inner furnace, which has made possible a long history of mountain building and plate tectonics, also necessary to maintain a suitable habitat for life. Finally the Earth was compositionally capable of producing a very thin outer crust of low density material which allows plate tectonics to operate. The thickness and stability of the Earth’s core, mantle and crust could only have come about by the most fortuitous assemblage of the correct elemental building blocks.” (Rare Earth, p. 50/1).

There’s that Anthropomorphic Principle again. It is nothing short of amazing how often it turns out that “fortuitous” circumstance lies at the core of all of the most essential ingredients of life, from the strength of gravity to our position in our galaxy (see previous posts on these topics). Can this all be circumstance or is it Design? But I digress: “The atmosphere was formed by out-gassing from the molten interior, which released volatiles originally carried to Earth in planetesimals bodies as well as by delivery from impacting comets. The composition and density of the atmosphere are influence by the amount and nature of the original accreted material of the Earth, and recycled by tectonic processes. The oceans of the Earth are a by-product of the out-gassing and formation of the atmosphere, and assist in regulating its composition.”

A self-regulating system, in other words. To this extent I agree with others who imagine that God started the Earth going and now simply watches benignly: the ‘God as Watchmaker’ view of the Creator. Certainly God has wisely and wonderfully made all things so that they could run without His having to do anything else. But that is not the God He has revealed Himself to be. He takes an active and personal interest in His creation, because He is an active and personal God. That may not be the current popular view of God, but then again, popular opinion never did count for much in the discovery of truth, did it?

It was popular opinion that the earth was flat, or perhaps sitting on the back of an elephant (Incidentally, that was never the Biblical view, anti-Christian slander notwithstanding. Three thousand years ago, long before Galileo, the Psalmist wrote that “God hung the world upon nothing”). Popular opinion now holds that the earth is an insignificant speck of dust with nothing to distinguish it. Proper scientific understanding teaches us otherwise. The earth with its remarkable sun and its amazing life-giving tectonic forces is perhaps the rarest thing in the universe, and we should certainly take better care of it.

We will be turning off our computer and lights now – not that we run much electricity anyway – and we encourage you to do the same. It won’t save much, all told, but it is a way of raising consciousness of the problems that we face as a global community.