In a passage added to the second edition of the Critique, Kant also points out that by arguing for the “transcendental ideality” of spatio-temporality—that it is a necessary feature of our representations of things but not a feature of things as they are in themselves at all—he does not mean to degrade space to a “mere illusion”, as did “the good Berkeley” (B 71): his position is that it is a subjective but necessary feature of our way of representing things, similar to secondary qualities such