For meaning theorists the process of secularisation in modern industrial societies is problematic, as it is for all theories that locate the source of religion in the human condition. Bellah has argued that the notion of secularisation forms part of a theory of modern society stemming originally from the Enlightenment reaction to the Christian religious tradition characterised by a strong cognitive bias and emphasis on orthodox belief. Whether modern society is secularised or undergoing a process of secularisation depends very much on what one means by religion and, therefore, by secularisation. From an extensive review of theories of secularisation Tschannen concludes that three core elements can be discerned which he terms differentiation, rationalisation and worldliness. The set of factors internal to the Christian tradition is stressed by Peter Berger in his influential analysis. Berger emphasises the tendency associated with increased rationality which Max Weber termed the ‘disenchantment of the world’.