Wilfred Bion was fascinated by the question “how are thoughts born?” He came back to it again and again, each time from a different perspective. According to his theory, the core from which thinking is formed is created in utero and when the baby is born, the core emerges into the world as a primordial kind of thought, which Bion calls a “preconception”. The baby, Bion asserts, comes into the world with a preconception about meeting a breast. The baby’s encounter with the mother in the beginning of life is the stage of fulfilment or, in Bion’s terms, the stage of realisation: something that the baby has been expecting has taken place. Bion’s Cogitations was published in 1992, thirty years after his theory of thinking came out. Several significant innovations to Bion’s theory of thinking can be found in Cogitations. The containing function is a function of thinking. Thoughts are born within the mother, in response to her baby.