Full Idea
Thinkers from Hume to the logical positivists took exception to Kant's view that some synthetic propositions could be known a priori, and so rejected the possibility of metaphysics as Kant conceived of it.
Gist of Idea
Humeans rejected the a priori synthetic, and so rejected even Kantian metaphysics
Source
report of A.J. Ayer (Language,Truth and Logic [1936]) by Cynthia Macdonald - Varieties of Things Ch.1
Book Reference
Macdonald,Cynthia: 'Varieties of Things' [Blackwell 2005], p.15
A Reaction
See Idea 7918 for Kant's epistemological view of metaphysics. This strikes me as a big misunderstanding by empiricists, even though they are quite right to insist on evidence and proof. Metaphysics is essential, but its excess is the worst nonsense.
Related Ideas
Idea 7918 Kant turned metaphysics into epistemology, ignoring Aristotle's 'being qua being' [Kant, by Macdonald,C]
Idea 16931 Metaphysics is generating a priori knowledge by intuition and concepts, leading to the synthetic [Kant]