Consider the premise. Does the hypothesis stand independently without contradicting or following it? Premise: After the purge of foreigners, only a few stayed on, strictly confined to Dejima Island in Nagasaki Bay. Hypothesis: A few foreigners were left free after the purge on foreigners.
After the purge of foreigners, only a few stayed on, strictly confined to Dejima Island in Nagasaki Bay.###A few foreigners were left free after the purge on foreigners.