grist to the mill

grist to the mill (uncountable)

1. (idiomatic, chiefly Britain) Alternative form of grist for the mill
   • 1875, Anthony Trollope, chapter 58, in The Way We Live Now:

     What evil will not a rival say to stop the flow of grist to the mill of the hated one?

   • 1999, Simon Blackburn, Think: A Compelling Introduction to Philosophy (Oxford University Press paperback, →ISBN, ch. 7 section 6: "Kant’s Revolution", pp. 258–259:

     This might all seem grist to Berkeley’s mill. Berkeley himself knew that we interpret our experience in spatio-temporal, objective terms. But he thought we had to ‘speak with the vulgar but think with the learned’: in other words, learn to regard that interpretation as a kind of façon de parler, rather than the description of a real, independent, objective world.

• Often found in the expression it's all grist to the mill and variations thereof.