The media extensions of man are the hominization of the planet; it is the second phase of the original creation.² 

McLuhan saw satellites as that particular ‘extension of man’ best illustrating such hominization:

Satellites (…) transform the planet into a work of art by placing it inside a man-made environment… (Take Today, 294)

When the planet was suddenly enveloped by a man-made artifact, “Nature” flipped into art form. (The End of the Work Ethic, Address to The Empire Club of Canada, November 16, 1972)

A satellite was a kind of mini-planet that could support life, like the planet beneath our feet, but one that was entirely “man-made”. It thereby prompted a different take on Earth itself and ecological consciousness was born:³

The moment of Sputnik was the moment of creating Spaceship Earth… (The End of the Work Ethic)

But even before Sputnik’s launch in 1957, McLuhan had seen the same phenomenon already at work since the scientific and industrial revolutions. Here he is already in Explorations 2 in 1954:

Technology has abolished ‘nature’ in the old sense and brought the globe within the scope of art. (Notes on the Media as Art Forms)⁴

In fact, once technology was conceived as the domain of human extensions, the abolition of nature and hominization of the planet must have occurred already with those first extensions of paleolithic “humanoids”, speech and stone tools:

The first humanoid uttering his first intelligible grunt, or “word,” outered himself and set up a dynamic relationship with himself, other creatures, and the world outside his skin. Speech (…) is (…) a tool to reconstitute nature (…) to translate one form [nature] into another [human experience and its collective expression in culture].⁵ (…) The pre-neolithic [= paleolithic] art of making stone tools [like the art of making speech tools] moved man out of the process of [natural] evolution and into a world of his own making. (The Global Village, 1989, p93)

Humans qua humans — humans as humans — are fundamentally creative in this way:

In ordinary perception men perform the miracle of recreating within themselves, in their interior faculties, the exterior world. This miracle is the work of the nous poietikos or of the agent intellect — that is, the poetic or creative process. The exterior world in every instant of perception is interiorized and recreated in a new matter. Ourselves. (Catholic Humanism and Modern Letters, 1954)

Hence, even with paleolithic “humanoids”, or especially with paleolithic “humanoids” (since a beginning exceeds the development it enables and shapes), a ‘new’ factor is operative in the world. Things no longer follow a purely ‘natural’ course. Through the exercise of creativity even, or especially, in “ordinary perception”, ever repeated leaps of creativity punctuate nature in such a way that the physical course of events is inter/rupted. 

“In every instant” ruptures occur. The gap is where the action is.

Here McLuhan is close to the Epicurean view of Lucretius (c99 BC – c55 BC) in De rerum natura:

Where do we get that freewill, wrenched away
From the fates, by which we each proceed to follow pleasure’s sway,
So that we swerve our motions not at a designated spot
And fixed time, but the very place we will it in our thought?
Without a doubt these motions have their beginning in the whims
Of each, and from that will these motions trickle into the limbs.⁶

With all living beings, but especially with humans, a decided clinamen (swerve) is seen to operate in the world alongside, but exceeding in some way, the world of nature, the world of the natural ‘course of events’.

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