The 2012 Founder's Lecture on Imagination and Testimony: Trusting What You're Told delivered by Professor Paul Harris, Harvard University, Emeritus Fellow and formerly Tutor in Experimental Psychology at St John's. The lecture took place on Thursday 10 May. Experimental work in psychology has traditionally focused on our capacity to observe and remember reality in a more or less veridical fashion. But recent research in developmental psychology has increasingly begun to analyze our human ability to set reality aside and to think about unobservable or fictional possibilities. Professor Harris will describe how this imaginative capacity emerges in early childhood, the key role that it plays in learning from what other people say and do, and its larger impact on our trust in historical, scientific and religious claims.