Every man got one poem, and when he stumbles on it he got to make it smaller and smaller and blacker and blacker and then it will finally convince.

Ad Reinhardt, hanging black canvasses. 

"Yet evidence suggests that Lax’s colour poems were not entirely uninfluenced by current events. On 15 September 1963, four young black girls were killed in a racist bomb attack while attending church in Birmingham, Alabama. In early October, Merton wrote Lax that he was “tired of belonging to the humiliating white race.” 

Reinhardt was a prominent subject of exchanges between Lax and Merton at this time. They discussed his participation in Civil Rights Marches, and writing from Greece, Lax declared himself present at the marches in spirit. Both were full of praise for their artist friend, and not just for his political activities. By this time Reinhardt had begun to paint his five-foot square black paintings exclusively. “Old Reinhardt is a splendid fellow and all but the king of the birds,” wrote Lax. “His paintings is magnificent and works like dynamite when set down in any particular locale. They are all black paintings (get it?) black, black, black & can hardly help doing some good in the whole situation.”  

In the midst of this conversation, Lax gave Merton some poetic advice:  “as reinhardt makes now all the time the same black painting, make you also all the time the same dark poem; all the time, just that one poem: here a word, there a word, maybe a little different; only when you think it should be, until it gets to be tight as a sonnet: the music, the music always the same, here a word, there a word just a little different.”  

“You got the right answers,” returned Merton, “I think this poem should get blacker and blacker and blacker like Reinhardt’s paintings, then everyone will see the light, they will have to. Every man got one poem, and when he stumbles on it he got to make it smaller and smaller and blacker and blacker and then it will finally convince.”  

Lax replied that he had “of recent months become so generally small & black myself that it is useless for me to apply for abrogation from the whites. How come you want to get out of the race (they would snigger) you was never in it.”" 

[This exchange took place between 5 October and 2 November 1963. See When Prophecy Still  Had a Voice, pp. 251-259.]

-from Karen Alexander's "The Abstract Minimalist Poetry of Robert Lax" http://www.cipa.ulg.ac.be/pdf/alexander.pdf