However, even in the classroom environment collaborative learning is not without its problems, there may be, for instance, students who dominate, passive students, students who are reluctant to present their ideas (particularly if these contradict the teacher's), or students doing no work at the expense of others. The online environment may actually help to mitigate some of these problems and lead students to perceive online group discussions as more democratic and equitable than the traditional classroom's counterpart (Swan, 2001). Some (e.g. Jonassen and Kwon, 2001 ; Lai, 1997) assert that subjects involving discussion, brainstorming or reflection are particularly suited to the online environment, and reflective learning - approaches that enable learners to reflect on their learning and their learning processes - may be especially effective in this context. An important element of reflective learning is that of reflecting upon knowledge in order to make it explicit. Social software, for example wikis, enables this reflection to take place collaboratively, bringing learning closer to the social constructivist ideal.