Some of the reasons that Descartes gave for his view that the pineal gland is the principal seat of the soul died out more slowly than this view itself. For example, his argument that “since our soul is not double, but one and indivisible, […] the part of the body to which it is most immediately joined should also be single and not divided into a pair of similar parts” (30 July 1640, AT III:124, CSMK 149), for instance, still played a role when Lancisi (1712) identified the unpaired corpus callosum in the midline of the brain as the seat of the soul. This view was, however, refuted by Zinn (1749) in a series of split-brain experiments on dogs. Lamettrie and many others explicitly rejected the thesis that the unity of experience requires a corresponding unity of the seat of the soul (Lamettrie 1745, ch. 10).