We present the best known separation between tree-like and general resolution, improving on the recent $\exp(n^\epsilon)$ separation of \cite{BEGJ98}. This is done by constructing a natural family of contradictions, of size $n$, that have $O(n)$-size resolution refutations, but only $\exp (\Omega(n/\log n))$-size tree-like refutations. This result implies that the most ... more >>>