Answer
The train stops at all stations.
Work Step by Step
There are infinitely many stations on a train route. Suppose that the train stops at the first station and suppose that if the train stops at a station, then it stops at the next station. Show that the train stops at all stations.
This set-up provides the information necessary to demonstrate the conclusion using induction. The stations can be labeled one-to-one using each integer, the base case is that the train stops at the first station, and if the train stops at station $n$, then it stops at station $n+1$. Thus, the train stops at all stations.
