The Pentagon Identity
Let $W$, $X$, $Y$ and $Z$ be sets. We have to show that the diagram
commutes. Indeed, this diagram acts on elements as
and thus the pentagon identity is satisfied.
The Triangle Identity
Let $X$ and $Y$ be sets. We have to show that the diagram
commutes. Indeed, this diagram acts on elements as
and thus the triangle identity is satisfied.
The Left Hexagon Identity
Let $X$, $Y$, and $Z$ be sets. We have to show that the diagram
commutes. Indeed, this diagram acts on elements as
and thus the left hexagon identity is satisfied.
The Right Hexagon Identity
Let $X$, $Y$, and $Z$ be sets. We have to show that the diagram
commutes. Indeed, this diagram acts on elements as
and thus the right hexagon identity is satisfied.
Monoidal Closedness
This follows from Chapter 2: Constructions With Sets, Item 2 of Proposition 2.3.5.1.2
Existence of Monoidal Diagonals
This follows from Item 1 and Item 2 of Proposition 3.1.8.1.2.