Rabbotai,
Today's daf says we learn from Yaakov avinu that a talmid chochom should not go out alone at night. We see that Yaakov Avinu did so and was harmed by the malach, saro shel Eisav.
Didn't we learn elsewhere that one of the signs that a person has the halachic status of shoteh is that he goes out alone at night (Tosefta teruma I think). It was very dangerous at least in Chazal's day.
That being the case, why does our gemara apply that to davka a talmid chochom? Why not apply that to everyone?
B'kavod,
Samuel Kosofsky
Regarding a Shoteh, the Gemara in Chagigah 3b states that merely going out alone at night does not qualify a person to be considered a Shoteh, as it could be that he is suffering from a panic attack (Rashi). The Gemara there mentions three characteristics of a Shoteh and says that only if he has all of them he is deemed a Shoteh. However, a Talmid Chacham is told not to go out alone for other reasons, since besides the element of danger involved, he could also be suspected of looking for illicit relationships (Berachos 43b).
The Poskim discuss your question of why a Talmid Chacham is singled out, since the Gemara in Pesachim 112b states that even an ordinary person should not go out on certain nights (a similar idea is mentioned in Pesachim 2a).
The Maharsha suggests that a Talmid Chacham must be more careful and even if he is going out to perform a Mitzvah, he should not go alone at night and cannot rely on his Torah to protect him.
The Turei Even suggests that the Shoteh refers only to a person who goes out alone in uninhabited areas at night, as this is more dangerous.
Yoel Domb