Since the reform and opening up, one of the highest slogans of philosophy is that practice is the only criterion for testing truth. This is not accidental, and grasping the problem of testing truth also grasps the key of all philosophical problems. It can be said that all philosophical problems are bound to be manifested as questions of testing truth in the end. All the differences between materialism and idealism are bound to show the difference of testing truth in the end.

Of course, in this sense, the development of truth is the main thing. Only in philosophy, the question of testing truth is more fundamental.

Truth can only come from practice, and truth can only be tested in practice. Here we need to know what this so-called practice is. I believe that the so-called practice, the most core and essential thing, is the combination of subjective and objective. People often ignore this essential thing in their understanding of practice, so we can't just correctly understand the truth from practice, and the truth can only be tested in practice.