Although these lectures discuss cancer they are also important to the larger topics of cell differentiation and morphogenesis. The Levin Lab is accumulating evidence suggests that voltage gradients across cell membranes determine gene expression (epigenetics) and morphophology/anatomy. The definition of cancer, in the present-day US at least, tends to emphasize the hypothesis that genetic changes lead to cancer. However, this hypothesis is challenged by evidence involving the transplanting of cancer nuclei into non-cancer cells and vice versa. Several features of cancer cells have been identified, and the key will creating a hypothesis that can link them all together.