Alan Garnham

We develop a criterion for telling when integrating two pieces of information, e.g. two pictures or statements requires an understanding of perspective. Problems that require such an understanding are perspective problems. With this criterion we can show that understanding false beliefs vis-à-vis reality pose a perspective problem, so does understanding spatial descriptions given from different viewing points (a classical example of what is commonly seen as a problem of perspective) and individuating objects with different sortals (naming objects). We use the result that understanding false belief as well as alternative naming of objects are both perspective problems to explain the otherwise inexplicable developmental finding that children master these two tasks at about the same time, around the age of 4 years.