in
the first place, how do we know [that the message on the
stone is the truth]? maybe somebody just wrote it as a joke.
in the second place, even if the message is true, suppose
we go into the forest and it gets dark before we find the
river. we probably wouldn’t be able to find the river at night.

여기서 would를 will의 과거형으로 보고 해석하면 되나요..?