Kant divides human knowledge into two parts, sensibility and understanding. Therefore, critical philosophy has to investigate two forms of a priori knowledge. In the first part of the Transcendental Analytic, which follows after the Transcendental Aesthetic, Kant states.
Li, Z. (2018). Epistemology: categories, in A new approach to Kant, Dordrecht, Springer, pp. 93-131.
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