Probable Values of the Cosmological Constant in a Holographic Theory

We point out that for a large class of universes, holography implies that the most probable value of the cosmological constant is zero. In four spacetime dimensions, the probability distribution takes the Baum-Hawking form, $dP\sim \exp (c{M}_p^2\mathrm{/}\mathrm{\Lambda })d\mathrm{\Lambda }$.