My source for “Humean Humility” is section 1.4.4 of Hume's Treatise of Human Nature, the section in which he gives his critique of“the modern philosophy.”
Hume contends that the world according to the modern philosophy—a world with primary qualities but no secondary qualities—is a world of which we can form no conception.There are echoes of Hume's premises (if not his conclusion) in two contemporary foci of philosophical attention: Russellian Monism, which agrees with Hume that there would be something defective in a world without anything like the traditional secondaries, but then, unlike Hume, goes on to attribute such qualities to the world, and Ramseyan Humility, which agrees with Hume that there must be more to any conceivable world than just structure with no underlying intrinsic or nonrelational properties, then goes on to argue that we could never know what these intrinsic properties are.
In what follows, I examine all three views, as well as the merits of several possible lines of reply to them, of which the most prominent is causal structuralism.31.1