Three tourists have an argument regarding the way they should go. Hans says that Emanuel lies. Emanuel claims that Hans and Philip speak the same, only doesn't know what, whether truth or lie.
So who is lying for sure?

The only one who is lying for sure is Philip. Hans speaks probably the truth and
Emanuel lies. It can be also the other way, but since Hans expressed himself before
Emanuel did, then Emanuel’s remark (that he does not know whether Hans is lying) is
not true.