Abstract
In this paper I focus on Kantian notions of 'idea' and 'system' and the pages that Alfredo Ferrarin dedicates to these topics in his book "The Powers of Pure Reason". In particular, I examine two key texts, namely the Appendix to Transcendental Dialectics and the Architectonics of Pure Reason in the "Critique of Pure Reason". Finally, I try to outline a comparison with Hegel's position and, in so doing, to illustrate two different ways of understanding the relationship between thought and reality.