Not All Knowledge is Usefull It is under discussion question that usefulness is not a quality of all knowledge. A person can not know everything and something does not just need to know. It is scientifically proved fact that a human`s brain can not know everything. A person`s abilities have boundaries. It is the reason why everyone chooses the knowledge that will be useful for him or her. For example, the knowledge of weapon`s varieties probably would not be worthwhile for an actor if he or she did not know a script. Moreover, a person who has deep knowledge in one area will be more successful than a person who knows something in many areas. That shows unusefulness of some knowledge for a person. Sherlock Holmes did not know the Solar system, but he was a professional in his deal. However, some people have a different opinion. They believe that a person may be successful only if he or she knows a lot. They guide by such examples of the people like Lomonosov, L. da Vinci who were educated in many subjects. It is true that they knew much, but it needs to be mentioned that they lived centuries ago. Nowadays a person is surrounded by information while the time when lived the people humanity did not have so much knowledge as now. It was able to remember all of it before. In conclusion, some information and knowledge indeed are not useful.