# Gossen's laws

Gossen's laws, named for Hermann Heinrich Gossen (1810 – 1858), are three laws of economics:

$\frac{\partial U/\partial x_i}{p_i}=\frac{\partial U/\partial x_j}{p_j}\,\forall\left(i,j\right)$
where
• $U$ is utility
• $x_i$ is quantity of the $i$-th good or service
• $p_i$ is the price of the $i$-th good or service
• Gossen's Third Law is that scarcity is a precondition for economic value.