This chapter discusses Paul Tillich's conceptual elaborations with regards to his philosophy of religion as well as his particular way of understanding metaphysics as a 'theoretical and universal function of meaning' that opens the door to a unique connection with the sciences. It presents several of his arguments in search of a method which is most favourable to the philosophy of religion and then attempt to reveal how Tillich develops his theology of culture, differentiating between content, form and substance of reality. It is not possible to speak with Tillich about a theology of culture without also considering the philosophy of religion and the history of cultural values. The chapter explores what Tillich means by 'the dimension of depth', as it is an inherent function of life; a part of the human being in all his possibilities and dimensions. It finally contrasts these arguments with regard to the current debate on the relationship between science and religion.