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We argue that flat space amplitudes for the process $ 2 \to n$ gravitons atcenter of mass energies $\sqrt{s}$ much less than the Planck scale, willcoincide approximately with amplitudes calculated from correlators of aboundary CFT for AdS space of radius $R\gg L_P$, only when $n < R/L_P$ . Forlarger values of $n$ in AdS space, insisting that all the incoming energyenters "the arena" [arXiv:hep-th/9901079], implies the production of blackholes, whereas there is no black hole production in the flat space amplitudes.We also argue, from unitarity, that flat space amplitudes for all $n$ arenecessary to reconstruct the complicated singularity at zero momentum in the $2\to 2$ amplitude, which can therefore not be reproduced as the limit of an AdScalculation. Applying similar reasoning to amplitudes for real black holeproduction in flat space, we argue that unitarity of the flat space S-matrixcannot be assessed or inferred from properties of CFT correlators.

Soft Gravitons and the Flat Space Limit of Anti-deSitter Space