10 Jan '15 16:52>
With two white hats and one black hat the tricksy black hatter can wait patiently for one of the white hatters to get up and announce incorrectly that his hat is black.
With one white hat and two black hats each black hatter cannot be sure that the other one is not tricksy, so neither declares.
With three black hats, none of the black hats can know that their hat is not white because if the other two stall it could also be one white and two blacks.
With one white hat and two black hats each black hatter cannot be sure that the other one is not tricksy, so neither declares.
With three black hats, none of the black hats can know that their hat is not white because if the other two stall it could also be one white and two blacks.