Walle sought to expand the notion of adventure by arguing that one can distinguish between two types: risk taking adventure and that which is pursued to gain knowledge and insight. While this expansion to incorporate insight seeking is useful, several comments in regard to his argument are in order. He refers to Maslow’s (1954) hierarchy of needs to point out contradictions between this and the prevalent risk theory of adventure, to open his argument for the need for the alternative insight theory. It is, however, important to note that Maslow’s theory itself has been questioned on several grounds. Cooper, Fletcher, Gilbert and Wanhill, for example, note that: