The Tosfot, in the Kol Hayad chapter, page 14b, wrote, in these words: One must also be precise about what Rabbi Hiyya said to Rabbi [Yehudah Hanassi], "You too consider it as a spot", and that he did not say, "You too, Master, consider it as a spot". Learn from this that he was in his elder years and was a collegiate student, as we said at the end of [the issue] "one who dies": "Ben Azai was a collegiate student of Rabbi Akiva, for he said to him: You sit, and did not say: Sit, Master". Meaning that had this been said during the years of Rabbi Hiyya's youth he could not have said to Rabbi, 'You too consider' and so on. We learn from this that a student who acquires substantial wisdom with his master, despite the fact that most of the wisdom is from the latter – is considered a collegial student.