This sentence means that history can be shaped and interpreted at will. Hu Shi believes that history is not an objective fact, but people's understanding and interpretation of past events. This view is contrary to the traditional view of history, which holds that history exists objectively and is not influenced by individual subjective will.
This view of Hu Shi reflects his critical attitude towards traditional culture. He believes that some concepts and methods in traditional culture are too conservative and rigid, which is not conducive to social progress and development. He advocated abandoning these old ideas and accepting new ideas and methods to promote China's modernization.
It should be noted that although Hu Shi put forward the view that "history is a little girl who can dress up", he did not completely deny the objectivity of history. In fact, he still believes that there are some universal laws and values in history, which can guide us to know and understand the past to some extent. However, he stressed that people should have the ability to think independently when interpreting history, rather than blindly accepting traditional concepts and explanations.