What kind of knowledge can be obtained during travel depends on the purpose of this person's travel.If his object is a philosophical system, then the traveler can see what he wants to see; if his object is personal gain, he naturally devotes his attention to everything connected with it.Business and technology strengthen the links between countries, but at the same time prevent them from learning from each other.Since all they think about is how to benefit from their neighbors, what else is there to think about?