Three of my children are medical doctors, they know at least a hundred times as much about your body as my grandfather knew, but they don’t know much more about soul than he did.

Templeton contrasts rapid advances in medical/scientific knowledge with the comparatively slow growth of wisdom about inner life. By noting that his physician children know vastly more about the body than his grandfather did, he underscores modernity’s success in accumulating technical, measurable information. The second clause—knowing “not much more about soul”—suggests that questions of meaning, character, purpose, and spiritual understanding are not automatically solved by progress in the sciences. The remark fits Templeton’s lifelong interest in bridging empirical inquiry and spirituality: it is a call to invest intellectual seriousness in moral and spiritual development, not only in material or biological mastery.