Consider the Cannibals & Missionaries Problem:
In the missionaries and cannibals problem, three missionaries and three cannibals must cross a river using a boat which can carry at most two people, under the constraint that, for both banks, if there are missionaries present on the bank, they cannot be outnumbered by cannibals (if they were, the cannibals would eat the missionaries). The boat cannot cross the river by itself with no people on board.
How to model this problem in First Order Logic?
I have been trying to model it for over 20 hours now, but I failed time again. Is there a resource available online or can someone help me?