This time, we have our two individuals contradicting each other. Someone is lying, and so someone must be a knave. You can see the original problem here.
If you assume the first person, A, is telling the truth, then B is a knave and must be lying. B says, «neither of us are knaves,» but if he is a knave as A claims then this is a lie, which checks out.
Alternatively, if you assume B is telling the truth when he says, «neither of us are knaves,» then they must both be knights. But A said, «B is a knave,» and if they are both knights then this is a lie, and knights, of course, never lie. So B cannot be telling the truth.
Therefore, A is a knight and B is a knave.
There are many more knights and knaves walking around this island, so make sure to come back next week for another conversation with them!
*See all of our riddles here.
Jay Bennett is the associate editor of PopularMechanics.com. He has also written for Smithsonian, Popular Science and Outside Magazine.