 From his mother and from maternal grandmother Ritsema inherited a religious disposition and a sense of being guided in life by God – indeed, of being carried in God’s arms.Ritsema’s father on the other hand, trained in chemistry and pursuing an abiding interest in biology, was by temperament a scientist and a rationalist thinker.At the age of 11 Ritsema entered the Odenwaldschule in Heppenheim, Germany, whose founders, Paul and Edith Geheeb, were to exert a profound influence on him.