Ezekiel starts by saying that at times, he is able to assume a philosophical attitude, a "cold lucidity" beyond everyday phenomena. This lucidity's "will is uncontrolled", i.e., everything is subsumed to this frame of mind. Defined as it is by excruciating clarity, in this state even the mills of God operate at speed, grinding very fine very quickly. The proverb about the mills of God grinding slowly means that consequences follow at a far remove from action. But in philosophy, consequences follow immediately, because they are an abstract, logical result rather than a human one.
Being pure mind, the philosopher is able to assume a godlike stance outside history, emotion, and even the universe. Nothing remains. The vastness of time and space that unfolds when he is in this attitude allows him to see all of existence as meaningless: the cosmos is just slime, and passions vanish in the blink of an eye.
In the second half of the poem, Ezekiel rejoins the rest of us on the quotidian plane, rejecting the cold comfort of philosophy. A philosophical attitude explains away pain. Consider, for example, the Buddhist attitude: all life is suffering; suffering is caused by attachment to impermanent things; give up attachment and suffering will cease; so will life, because one will attain Nirvana, literally a snuffing-out of existence. This is a wonderfully logical argument, but its clarity dismisses everyday human experience. The pangs of an illness? Health is not a permanent condition, and it's foolish to expect to avoid sickness. The death of a loved one? Everybody dies, and it's foolish to have expected not to be parted. Any sorrow becomes trivial and meaningless from a philosophical standpoint, because human beings are insignificant and human existence meaningless when seen against the grand vistas of infinity and eternity. Human beings suffer all the same.
Ezekiel avers that providing philosophical explanations for this suffering is beside the point. He insists that "residues of meaning still remain" even as pain is rendered meaningless in the philosophical "formula of light". And like those residues, he, too, calls into question "this clarity of sight". He rejects the rationalism of the first half of the poem and embraces empiricism, the "mundane language of the senses". The very ordinariness of human existence clothes us, keeping us warm and alive against the cold light of philosophical truth. The last stanza of the poem strikes me as one of the greatest ever written.
Ezekiel's attentiveness to poetic detail allows the poem to enact the truth of its argument: mere fripperies are nevertheless meaningful. His control over rhyme and meter, syntax and vocabulary are superb. Take the lines:
... I think
Of each historic passion as a blink
That happened to the sad eye of Time.
Passion can mean love, anger, desire, or lust; it can also mean suffering and death, as in the passion of Christ. From the philosopher's perspective, all those are the same, a passion being merely something that happened. What an unusual word to apply to a passion! Driving home the point, one doesn't say a blink "happened" either. To say that something happened in the blink of an eye would be cliche, except that what happened was a passion and the blink happened to the eye. And not just any eye: the eye of Time. Ezekiel's handling of tone here beggars description. The line is deliciously funny as it yokes together the incongruity of something as trivial as a blink happening to something as grandiose as the eye of Time. But from the vantage of eternal time, all human endeavor is incongruous, simultaneously trivial and grandiose. Like poetry, or, for that matter, philosophy.