Clause 1 gives the situation at the start of the puzzle. The clause says that three missionaries and three cannibals are on the west bank, and zero of each is on the east.

Clause 2 says that the west bank now has three missionaries and two cannibals there, while the east now has zero missionaries and one cannibal.

Clause 3 depicts the boat trip that takes one cannibal and no missionaries from the east bank to the west bank. It also takes into account that the number of cannibals on the west bank must increase, while the number on the east bank decreases.

Clauses 4 through 11 cover the other possible boat trips from west bank to east, and back.

Clause 12 expresses the unachievable state that corresponds to assuming the puzzle unsolvable.

Clauses 13 through 16 take care of situations to be avoided, such as having two missionaries and three cannibals.