Some people describe natural science as "hard science" and social science as "soft science." And there are also people who describe natural science as "easy science" because it is easy to control and define--being that everything can be measured--and social science as "difficult science" because the variables are many and it's hard to control.
有人稱自然科學為「硬調科學（hard science）」、稱社會科學為「軟調科學（soft science）」；也有人稱自然科學為「容易的科學（easy science）」，因為很容易操作，可以完全量化，而社會科學就是困難的科學，處理的變項很多，不容易操作。