  The Fermi paradox is the conflict between an expectation of a high {\em ex
ante} probability of intelligent life elsewhere in the universe and the
apparently lifeless universe we in fact observe. The expectation that the
universe should be teeming with intelligent life is linked to models like the
Drake equation, which suggest that even if the probability of intelligent life
developing at a given site is small, the sheer multitude of possible sites
should nonetheless yield a large number of potentially observable
civilizations. We show that this conflict arises from the use of Drake-like
equations, which implicitly assume certainty regarding highly uncertain
parameters. We examine these parameters, incorporating models of chemical and
genetic transitions on paths to the origin of life, and show that extant
scientific knowledge corresponds to uncertainties that span multiple orders of
magnitude. This makes a stark difference. When the model is recast to represent
realistic distributions of uncertainty, we find a substantial {\em ex ante}
probability of there being no other intelligent life in our observable
universe, and thus that there should be little surprise when we fail to detect
any signs of it. This result dissolves the Fermi paradox, and in doing so
removes any need to invoke speculative mechanisms by which civilizations would
inevitably fail to have observable effects upon the universe.
