The Talmud tells us that when Resh Lakish -- Rabbi Simeon ben Lakish -- died, Rabbi Jochanan was inconsolable. No one else challenged Rabbi Jochanan's conclusions so vigorously or engaged him in such sharp argument. Repeatedly the Jewish tradition emphasizes that disagreement, even fundamental disagreement, need not be the same as personal hostility.
I have engaged in debates with some very sharp antagonists over the years, including with some noted atheists -- Christopher Hitchens, Sam Harris, Steven Pinker. The differences were deep and fundamental. Yet in no case was the exchange, however charged, tinged with personal animosity. The relationships remained cordial and even friendly, although our disagreements could not have been more pronounced.
Throughout Jewish history argument has been elevated as a means of discovering truth. Every student of Talmud grows accustomed to the exchanges across centuries, as claims and debates contend for primacy. At times debate can indeed become heated; but in the end, the aim is truth.
Edmund Husserl once said of his fellow philosopher Lev Shestov, "No one has ever attacked me so sharply as he. That's why we are such close friends." I like to think that the Jewish background of both philosophers had something to do with their willingness to argue and remain friends. Resh Lakish and Rabbi Jochanan would understand.