#### Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Options

# Exercise 31 - Chapter 4

edited June 8

Prove Lemma 4.30. (Hint: remember to use the fact that $$\mathcal{V} is skeletal.) Lemma 4.30 Serial composition of profunctors is associative: given profunctors \( \Phi : \mathcal{P} \rightarrow \mathcal{Q}$$, $$\Psi : \mathcal{Q} → \mathcal{R}$$, and $$\Upsilon : \mathcal{R} → \mathcal{S}$$, we have $$(\Phi.\Psi).\Upsilon = \Phi.(\Psi.\Upsilon)$$