In the US and most of the world, horse races are just about always conducted counter-clockwise, and this was true in Ryder's time as well (I googled). It therefore seems appropriate to notice and emphasize, as the poem does, that death is a "clockwise rider", breaking off from the counter-clockwise track of the living.

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I'll tell you why: I was/am/might still be spatially disoriented. I saw the horse and rider as going in the "wrong" direction and conflated that with going counterclockwise.

You then also said: "In the US and most of the world, horse races are just about always conducted counter-clockwise, and this was true in Ryder's time as well (I googled). It therefore seems appropriate to notice and emphasize, as the poem does, that death is a "clockwise rider", breaking off from the counter-clockwise track of the living."

Which makes me think I am bucking death — Ha!

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I like the vilanelle structure and the line “candescent jockey. Psychopomp by name.” I don’t fully understand the meaning of the poem but I do like the reference to the painting. I like the subtlety of using counter clockwise rider since he is dead and going the opposite direction. The words laissez-faire, smart money makes me think this is a political critique of sort? The odds are in your favor - maybe the upper class since this is horse racing and the upper class are the ones that can afford to gamble on horse racing. “Of course the serpent startles at the game.” this makes me think of biblical sin imagery especially since the painting is referencing death, but who does the serpent represent? Maybe I’m overthinking this and this is just putting the imagery of the painting into words.