Since the publication of Dynamic Basis of Geomorphology by Arthur Stahler (1952) geomorphology has become dominated by the process approach to inquiry. This approach treats geomorphological processes and process-form interactions as manifestations of mechanical stresses and strains acting on earth materials. Little attention has been given to the philosophical underpinnings of this approach, which correspond to the doctrine of mechanistic materialism. Concerns about limitations of the process approach have been raised recently, including its inherent reductionism; difficulty in dealing with complex, large-scale geomorphic phenomena; and lack of a historical focus. This article presents an alternative perspective on the dynamic basis of geomorphology grounded in process philosophy. The central theme of process philosophy is that processes are ontologically and epistemologically more primary than substantive material objects. A major implication of process philosophy is that mechanistic concepts, while epistemically valuable, represent abstractions that lack ontological depth. Evidence both from contemporary science and from human experience suggests that the notions of matter as unchanging substance and of dynamic change as matter in motion under mechanistic influences are flawed ontologically. Instead, this evidence indicates that the nature of reality, including geomorphological phenomena, is fundamentally processual. By casting aside the constraints of mechanistic materialism, a process perspective grounded in process philosophy embraces the entire spectrum of research in contemporary geomorphology and has the potential to open new avenues of thought and inquiry, perhaps in ways that may also lead to enhanced connections between human and physical geography.