Where can I read Kant's view of thinking as willing, spontaneity and re-presenting?

Question

I am reading Martin Heidegger's Discourse on Thinking. At the beginning of "Conversation on a Country Path About Thinking*, the Scholar remarks: (page 58-9)

But thinking, understood in the traditional way, as re-presenting is a kind of willing. Kant, too, understands thinking this way when he characterizes it as spontaneity. To think is to will, and to will is to think.

The Teacher in this conversation doesn't agree that thinking is willing. In order to understand this better, I want to read what Kant has to say about thinking, willing, spontaneity and re-presenting.

Where can I find that in Kant's writings?

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Heidegger, M. Discourse on Thinking. Translation John M. Anderson. 1966.

Answer 1

Maybe the best place to start is Heidegger's own commentaries on Kant :

(1) What is a thing?

(2) Kant and the problem of metaphysics.

(3) and also Phenomenological interpretation of the Critics of pure reason.

Sure there are explanations in these references about thought as representation. Not absolutely sure Heidegger explains there in which way ( according to Kant) representation can be identified to willing.