The speaker's isolation is self-imposed. His relief on coming out of the lecture room is like that of a person getting off of a crowded bus. The speaker wants to learn about stars, but he's not interested in what society considers "knowledge." When he goes outside, however, he can "wander" wherever he wants. In the end, he really isn't so isolated after all because of the connection he feels with the outside world. But the question remains: can this connection last?
The speaker's mystical revelation is dependent on his solitude.
The speaker's mystical revelation is not dependent on his solitude. In fact, it points vaguely toward a communal utopia.