• Since $X\cong \bigvee _{x\in X^{-}}S^{0}$ and $\otimes _{\mathsf{Sets}_{*}}$ preserves colimits in each variable, we have
    \begin{align*} X\otimes _{\mathsf{Sets}_{*}}Y & \cong \webleft (\bigvee _{x\in X^{-}}S^{0}\webright )\otimes _{\mathsf{Sets}_{*}}Y\\ & \cong \bigvee _{x\in X^{-}}\webleft (S^{0}\otimes _{\mathsf{Sets}_{*}}Y\webright )\\ & \cong \bigvee _{x\in X^{-}}Y\\ & \cong \bigvee _{x\in X^{-}}S^{0}\wedge Y\\ & \cong \webleft (\bigvee _{x\in X^{-}}S^{0}\webright )\wedge Y\\ & \cong X\wedge Y, \end{align*}

    naturally in $Y\in \text{Obj}\webleft (\mathsf{Sets}_{*}\webright )$, where we have used that $S^{0}$ is the monoidal unit for $\otimes _{\mathsf{Sets}_{*}}$. Thus $X\otimes _{\mathsf{Sets}_{*}}-\cong X\wedge -$ for each $X\in \text{Obj}\webleft (\mathsf{Sets}_{*}\webright )$.


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