"Variability" and "fractality," two key concepts in Complex Dynamic Systems Theory (CDST)--the former concerning changes and variations, and the latter concerning recursiveness and self-similarities--may seem contradictory at first glance. This forum piece attempts to elucidate how the two seemingly contradictory properties can be reconciled in CDST to examine second language (L2) development. To that end, this piece includes a definition and short epistemological history of each concept, accompanied by a review of some relevant studies. It concludes with two metaphors to illustrate the relationship between "variability" and "fractality," and how the two seemingly irreconcilable ideas can generate a clearer and more panoramic view of L2 development.