There has been an act of what amounts to collective forgetting about air. Air has become a sort of vacuum—a strange paradox. There is, it seems, no air between us and the distant hills turning them blue; it is the hills themselves that are blue, or so we have fallen into the habit of thinking.
And yet air is the most intimate part of the natural world. It interpenetrates us; it is that part of the external world that most fully invades us. This air that circles the globe is also a component of my body, as essential and as internalised as my bones, my spleen, my heart. The sky over France is a huge extension of a part of my body that is rooted next to my heart. Air, in other words, is the only one of my body’s organs that is both common and ubiquitous. People on the other side of the planet are internalising my organ, as I theirs. The blowing of the winds is the most communal, orgiastic and deep-throated of blow-jobs.
Our thoughts about air see it as a medium, as the neutral and invisible solvent by which everything else is carried: sound waves travel in air (as if sound waves could be separated out from air! Say rather that sound waves are air); pollution is ‘air-borne’, as if air is the pure white packhorse and ‘pollution’ is the dirty sack of coals across its saddleback. This sort of thinking doesn’t help us. Pollution, in fact, is simply one of the manifestations of air. Thinkers who have long since chased away the superstitious old habit of thinking in terms of ‘appearance and reality’, of ‘phenomenal and noumenal’, of ‘truth and representation’ still assume this structure of thought with respect to the air they breathe. Freeing this sort of thinking from ‘air’ will open the windows.
So, for example, if we talk of ‘clouds existing in the air’, it implies that they might exist outside the air. But clouds are air, another one of its many protean forms.
To be more specific on this question: by talking of ‘the five senses’ we tend to hypostise the sensed material; so ‘a sense of smell’ implies that there is a material substance out there called ‘smell’ that our sense apprehends. This is not quite the case. ‘Scent’ is not some pure, ideal quantity that is carried ‘on the air’; it is, once again, one of the many forms of air. Similarly, sound waves can no more be separated from the air than ocean-waves can from the ocean. What would a ‘pure’ ocean-wave look like, the isolated ‘content’ separated from the ‘form’ of the sea? Perhaps we are tempted to think the answer to that question in terms of ‘information’, but that doesn’t get us any further, because information is always already embodied in one or other material form. There’s no such thing as ‘pure’ information.
Our sense of taste is closely bound up with our sense of smell; and the nerve-endings that mediate our sense of touch are fine-tuned for operation in air (although, of course, it is possible to feel pressure and temperature without air; but that's the crudest manifestation of the sense). This is to say: air shapes four of our senses. Only sight is exceptional, and it is so in interesting ways. So: the lunar astronaut only hears, only smells and tastes, only feels by virtue of the envelope of air inside his or her spacesuit, but he or she can see the stars without air. From this follow several interesting consequences.