"The never-ending debates over the central concepts of philosophy" have as their function "to ensure intellectual vitality across the whole spectrum of human knowledge." W.B. Gallie, preface to Philosophy and Historical Understanding.
I am not sure that Gallie is right that vitality is ensured by debate. Ultimately, his idea about what ensures vitality is more complicated, something like : 'a combination of debate and committed action arising out of debate.' He thinks that vitality emerges when people try to live out different conceptions of "democracy" or "rationality" or "tolerance," to show those on the other side of the debate: this is what it really means. I am not sure he is right even in his more complex view. But I am quite sure that vitality matters, that the standards for "good debate" or "good intellectual life" are not internal or technical standards. One can make lots of reasonable points in a dead debate. The question worth asking is: which debates are alive and which are dead? Where does intellectual life have vitality, and what does that mean? How can intellectual life intertwine with other kinds of life so that life as a whole has vitality?