In the paper Peter Sloterdijk is portrayed as a philosopher of elements who tries to correct the traditional philosophical reliance on earth by focusing on the elements air and water. The paper discusses the role that the latter element plays in Sloterdijk's philosophy. It is argued that it is crucial to understand this role in order to come to grips with what Sloterdijk himself has referred to as his ‘amphibious’ anthropology. The human animal does not prefer one element but switches from one element to the other.