Numbers and number sequences have enabled ways to conceptualise life, multiplicity and complexity. This chapter explores the symbolic significance of number including that of the tetraktys and the dynamic meaning of the Axiom of Maria and considers the way number has been used to represent creation, emergence, complexity and the symbol of the quintessence. The chapter considers how Jung examines number in terms of the way they can represent the dynamics of the self, relationship and an archetype of order. Overall this chapter looks at the way number is a representational symbol in which its quantitative features have become linked to symbols with qualitative and dynamic characteristics.