Rigor and Cognitivity

Some say philosophy lacks rigor.  Well, some does, but the best doesn't.  People who bemoan a lack of rigor in philosophy are typically unacquainted with its best authors.  The problem with philosophy is not lack of rigor but lack of cognitivity.  The lack of cognitivity, however, does not detract from philosophy's value.  Is there no value in the Socratic docta ignorantia?