Philosophically speaking, the opposition and unity of the two sides of the contradiction are inseparable, and the lack of any one aspect cannot constitute a contradiction. Wang Anshi only saw opposition without unity.

Because Wang Anshi said this sentence is based on the objective reality of physics. Wang Ji's view is based on Hegel's sophistry philosophy or human emotional and psychological feelings rather than modern scientific views.

But in fact, no sound is always quieter than sound. Wang Ji's view is just the opposite, so Wang Anshi's view conforms to modern logic and science.