How might Kant's 'noumenon' concept provide a critical response to earlier Western metaphysical thought concerning the knowledge of ultimate reality?

Immanuel Kant's concept of 'noumenon' represents his critical approach to metaphysics, particularly in response to the claims of knowing ultimate reality made by previous metaphysical philosophies. Kant introduces this concept to distinguish the things as they are in themselves ('noumena') from the things as they appear to our senses ('phenomena'). According to Kant, noumena cannot be directly known because our understanding is limited to the realm of experiences and phenomena; thus, we cannot have direct access to things-in-themselves.

This standpoint offers a critical perspective on earlier Western metaphysical thought, which often posited that the true nature of reality could be fully comprehended or described by human reason. Kant argued that many metaphysical disputes arise from the mistake of extending knowledge beyond the limits of possible experience and treating concepts as if they have an objective, concrete reality independent of our sensory experience.

For further reading, Kant's 'Critique of Pure Reason' is a foundational text discussing these ideas in depth: Critique of Pure Reason - Cambridge Core