Original sentence: In 1938, Shachtman shocked Trotsky by publishing an article in the New International in which James Burnham declared his opposition to dialectical materialism, the philosophy of Marxism.Many of those who had left the SWP did not join the Workers' Party: according to George Novack, a member of the Cannon/Trotsky faction, around half did.The case against Burnham and Shachtman's position is reflected in books by Cannon and Trotsky.Trotsky's review of some of the differences, From a Scratch to the Danger of Gangrene, suggests that these differences deepened after Trotsky's criticism of Shachtman's approach to the SP
Edited sentence: In 1939, Shachtman shocked Trotsky by publishing an article in the New International in which James Burnham declared his opposition to dialectical materialism, the philosophy of Marxism.Many of those who had left the SWP did not join the Workers' Party: Novack's recollection  is that around half did.The case against Burnham and Shachtman's position is reflected in books by Cannon  and Trotsky.Trotsky's review of some of the differences, From a Scratch To the Danger of Gangrene , suggests that these differences deepened after Trotsky's criticism of Shachtman's approach to the SP