At the beginning of the twentieth century, a new science, experimental psychology emerged, (6) ………. the speculative theories of the past were confirmed or disproved by the scientific method. At the forefront of this research was J B Watson. His area of interest was the origin of human (7) ……… Do we learn them, or do we have them when we are born? In particular, Watson wanted to study fear, and was prepared to go to (8) ……… lengths to study his theory.