I was just reading the author’s introduction to “Immanuel Kant: Prolegomena to Any Future Metaphysics” in the book “The Great Works of Philosophy” by Robert Paul Wolf [1]. I want to share the last section (pp. 347-348) of this 3-page intro:

“…If the  mind imposes its own subjective forms on nature, then the nature it knows cannot be a realm of things as they are in themselves; it must be merely a realm of things as they appear to us. In short, our knowledge must be limited to appearances; reality is forever obscured from our view. Hence metaphysics, the “science of reality,” must be an empty discipline, a mere pretension and illusion to be refuted rather than encouraged.
Thus Kant’s philosophy is at one and the same time optimistic and pessimistic. He reassures us that our mathematics and science is valid knowledge, but he cautions us that it is valid only for appearances, not for reality itself. In the end, the transcendental philosophy is a lesson in intellectual humility, for it teaches us that the human mind lacks the power to penetrate the veil of appearance and grasp the inner nature of independent reality.”

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