  We introduce a notion of Jacobi-Bernoulli cohomology associated to a
semi-simplicial Lie algebra (SELA). For an algebraic scheme $X$ over $\C$, we
construct a tangent SELA $\t_X$ and show that the Jacobi-Bernoulli cohomology
of $\t_X$ is related to infinitesimal deformations of $X$.
