If, like me, you didn't get the joke at first:
Both of the first two logicians wanted a beer; otherwise they would know the answer was "no". The third logician recognizes this, and therefore knows the answer.
Both of the first two logicians wanted a beer; otherwise they would know the answer was "no". The third logician recognizes this, and therefore knows the answer.
This way is logically most efficient to work and involve the least communication.
() In a lecture by the mathematician & author Sarah Hart.