The Welfare Theorems

A competitive equilibrium with transfers for the economy $\mathcal E$ is an allocation $(x^∗,y^∗)$, a price vector $p∗$ and an assignment of wealths $(w_1^∗, . . . , w_I^∗)$ to consumers such that

1. For every firm $m$, $y^*_m$ maximizes profits among all feasible production plans in $Y_m$: \begin{equation*} p^*y^*_m\geq p^*y_m\quad\mbox{for all}\quad y_m\in Y_m. \end{equation*}

2. For every consumer $n$, $x^*_n$ is preference-maximal among all affordable consumption plans. That is, $x^*_n\succeq_n x_n$ for all $x_n$ in the set \begin{equation*} \{x_n:x_n\in X_n\quad\mbox{and}\quad p^*x_n\leq w^*_n\}. \end{equation*}

3. $(x^*,y^*)\in A$.

4. $\sum_nw^*_n=\sum_np^*\omega+\sum_mp^*y^*_m$.