Three wise men set out on a journey for, even though they were considered wise in their own country, they were humble enough to hope that travel would broaden their minds.
They had barely crossed into a neighbouring country when they saw a skyscraper in the distance. What could this enormous object be, they asked themselves? The obvious answer would have been: go up and find out. But no, that might be too dangerous. Suppose it was something that exploded as one approached? It was altogether wiser to decide what it was before finding out. Various theories were put forward, examined and, on the basis of their past experience, rejected. Finally, it was determined, also on the basis of past experience of which they had an abundant supply, that the object in question, whatever it was could only have been placed there by giants.
This led them to the conclusion that it would be safer to avoid this country altogether. So they went back home having added something to their fund of experience.