premise: Eric has only visited Saint Vincent & the Grenadines, Brad has only visited Switzerland, Terrance has only visited Côte D'ivore, Nathaniel has only visited Yemen, Dan has only visited Eritrea, Roberto has only visited Burkina, Ken has only visited Argentina, Karl has only visited The Bahamas, Melvin has only visited Canada, Leslie has only visited Tunisia, Gilbert has only visited Finland, Wayne has only visited Timor-Leste
hypothesis: Melvin didn't visit Canada