 This is compatible with (Humility*) because we can know it merely by knowing that being spatial is an extrinsic property in general (thus is not an intrinsic property had by substances), and to know this we do not need to know anything about the intrinsic properties of substances. Langton thus offers a consistent, elegant interpretation of transcendental idealism that solves several of the oldest and hardest problems in the interpretation of Kant’s  philosophy.[48]