Organism Earth: The Gaia Theory...

The Gaia Hypothesis:

"The entire range of living matter on Earth from whales to viruses and from oaks to algae could be regarded as constituting a single living entity capable of maintaining the Earth's atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts...A complex entity involving the Earth's biosphere, atmosphere, oceans, and soil; the totality constituting a feedback or cybernetic system which seeks an optimal physical and chemical environment for life on this planet."

"To what extent is our collective intelligence also a part of Gaia? Do we as a species constitute a Gaian nervous system and a brain which can consciously anticipate environmental changes?" -James Lovelock (1960s).

"Earth is a perfect planet for life but, according to Gaia theory, this is no coincidence. From the moment life first appeared on Earth it has worked hard to make Earth a more comfortable place to live. Gaia theory suggests that the Earth and its natural cycles can be thought of like a living organism. When one natural cycle starts to go out of kilter other cycles work to bring it back, continually optimising the conditions for life on Earth.

Named after the Greek Earth goddess, Gaia, the theory was developed in the 1960s by scientist Dr James Lovelock. At the time, Lovelock was working for NASA, looking at methods of detecting life on Mars. The theory came about as a way of explaining why the Earth's atmosphere contains high levels of nitrogen and oxygen.

Initially, Gaia theory was ignored, and then later ridiculed by scientists such as Richard Dawkins and Stephen J Gould. However, in recent times stronger evidence for the theory has emerged and Gaia has started to gain support. The theory helps to explain some of the more unusual features of planet Earth, such as why the atmosphere isn't mostly carbon dioxide, and why the oceans aren't more salty.

In its early years Earth's atmosphere was mostly carbon dioxide - the product of multiple volcanic burps. It wasn't until life arrived that the balance began to change. Bacteria produced nitrogen, an inert gas, and photosynthesising plants produced oxygen, a very reactive gas. Ever since that time, about 2,500m years ago, Earth's atmosphere has contained significant amounts of nitrogen and oxygen, supporting life on this planet. The nitrogen helps to keep things stable, preventing oxygen levels from climbing too high and fuelling runaway fires. Meanwhile, the oxygen supports complex life.

Gaia also helps to explain how the oceans are kept in balance. Rivers dissolve salt from rocks and carry it to the ocean, yet ocean salinity has remained at about 3.4% for a very long time. It appears that the salt is removed again when water is cycled through cracks on the ocean floor. This process keeps the oceans' salinity in balance and at a level that most lifeforms can tolerate.

These processes are not thought to be conscious ones, or to favour any one life form over another. Gaia theory simply maintains that Earth's natural cycles work together to keep the Earth healthy and support life on Earth.

Lovelock argues that humans have now pushed Gaia to her limit. In addition to filling the atmosphere with carbon dioxide, we have hacked our way through the "lungs" of the planet (the rainforests) and driven many species to extinction. He thinks we are heading for a very warm world, where only polar regions are comfortable for most life forms. Eventually, he suspects, Gaia will pull things back into check, but it may be too late for the human race.

Feedback Loops:

Feedback loops often appear to keep the planet in balance. One good example of this is the way in which atmospheric carbon dioxide is kept in check. Carbon dioxide is pumped into the atmosphere by volcanoes, and removed by the weathering of rocks (encouraged by bacteria and plant roots in the soil). When it reaches the sea, the dissolved carbon dioxide is used by tiny organisms, known as coccolithophores (algae), to make their shells. When coccolithophores die they release a gas - dimethyl sulphate - which encourages the formation of clouds in the atmosphere.

When atmospheric carbon dioxide levels become too high, coccolithophores get busy, locking up more carbon dioxide in their shells and pumping dimethyl sulphate into the atmosphere when they die - producing clouds which reflect back sunlight and help the Earth to cool. Conversely, if atmospheric carbon dioxide levels become low, coccolithophores reduce their activity. Over the past 200 years mankind has greatly increased atmospheric carbon dioxide levels, and recently there has been evidence that algal blooms in the ocean are increasing. Could Gaia be trying to correct our mistake?

The Gaia Hypothesis has often been described by commentators as one of the most provoking singular ideas to have been put forward in the second half of the 20th Century."

-Kate Ravilious ("Perfect Harmony," Guardian UK, 4.28.2008. Image:-Hieronymus Bosch, Detail from the Triptych: "Garden of Earthly Delights", Museo del Prado, Madrid, 1500 ).

John Locke: The Tabula Rasa, An Exercise Of Power...

Of Practice And Habits:

"We are born with faculties and powers capable almost of anything, such at least as would carry us farther than can easily be imagined: but it is only the exercise of those powers which gives us ability and skill in anything, and leads us towards perfection.

The legs of a dancing- master and the fingers of a musician fall as it were naturally, without thought or pains, into regular and admirable motions. Bid them change their parts, and they will in vain endeavor to produce like motions in the members not used to them, and it will require length of time and long practice to attain but some degrees of a like ability. What incredible and astonishing actions do we find rope- dancers and tumblers bring their bodies to ! Not but that sundry in almost all manual arts are as wonderful; but I name those which the world takes notice of for such, because on that very account they give money to see them. All these admired motions, beyond the reach and almost conception of unpracticed spectators, are nothing but the mere effects of use and industry in men whose bodies have nothing peculiar in them from those of the amazed lookers-on.

As it is in the body, so it is in the mind: practice makes it what it is; and most even of those excellencies which are looked on as natural endowments, will be found, when examined into more narrowly, to be the product of exercise, and to be raised to that pitch only by repeated actions."

-John Locke (1632–1704: An English philosopher. Locke is considered the first of the British Empiricists, but is equally important to social contract theory. His ideas had enormous influence on the development of epistemology and political philosophy, and he is widely regarded as one of the most influential Enlightenment thinkers, classical republicans, and contributors to liberal theory. His writings influenced Voltaire and Rousseau, many Scottish Enlightenment thinkers, as well as the American revolutionaries. This influence is reflected in the American Declaration of Independence Locke's theory of mind is often cited as the origin for modern conceptions of identity and "the self", figuring prominently in the later works of philosophers such as David Hume, Jean-Jacques Rousseau and Immanuel Kant. Locke was the first philosopher to define the self through a continuity of "consciousness". He also postulated that the mind was a "blank slate" or "tabula rasa"; that is, contrary to Cartesian or Christian philosophy, Locke maintained that people are born without innate ideas."

Excerpt: Of Practice And Habits from The Educational Writings of John Locke, "Of The Conduct Of The Understanding" published posthumously, 1706. Bio: -Carl Lotus Becker, "The Declaration of Independence: A Study in the History of Political Ideas,"1922. Forrest E. Baird & Walter Kaufmann, "Plato to Derrida," 2008. Image: Philippe Petite's foot on wire between Twin Towers 1 & 2, New York, NY, 8.7. 1974).