Just as with “Abced-mindedness“, McLuhan deploys the “Vacuum of the Self” in two fundamentally different ways.  But these two ways are not opposed as two poles at odds with one another.  Instead, one considers everything in terms of such mutually exclusive poles and the other does not.

The “vacuum” considered in The Book of Tea has the characteristic action of ‘giving way’: the water pitcher gives way to water and to its management in being stored and carried and poured:

The usefulness of a water pitcher dwelt in the emptiness where water might be put, not in the form of the pitcher or the material of which it was made. Vacuum is all potent because all containing.” (Okakura Kakuzō, The Book of Tea, as cited in ‘The Brain and the Media’, 1978, and the posthumous Laws of Media, 78)

 Such a “vacuum” essentially gives way to what is not vacuous and so expresses itself in and as what the other sense of “vacuum” would consider to be complete opposites (the vacuum vs material stuff).

This difference is so fundamental that it even applies to the two senses or poles of the “vacuum” itself. The sense of “vacuum” as empty and annihilating considers the other sense of “vacuum” as replete and enabling to be its utter opposite — an utter opposite that in its view is nonsensical. But the sense of “vacuum” as replete and enabling considers the other sense of “vacuum” as empty and annihilating to be what most expresses its fundamental creativity and communicability, what most demonstrates how strangely essential it is to it — to give way.

The replete is so replete that it gives way even, or especially, to the empty.