First, the cultural background is different. Everyone's cultural education since childhood is different from their accumulated cultural background. In other words, there are different understandings of the same thing. For a person with profound cultural background, when looking at the same calligraphy work, he will understand it from the artistic conception and techniques of this calligraphy work. But for most people, when reading calligraphy works, because they don't understand the creation process and how to create, they often don't understand and feel nothing. This is the difference in cognitive level between the two sides. Looking at something without a certain background is like looking at a blank sheet of paper.
Second, professional knowledge As the saying goes, an expert looks at the doorway and a layman looks at the excitement. If you don't have professional calligraphy skills, that is, you don't have professional calligraphy knowledge, then you can't see anything when you look at calligraphy works. Professionals will judge the pros and cons of calligraphy from a professional perspective, while people who don't understand will often feel good when they see beautiful calligraphy works, and will often feel bad when they see ugly calligraphy works. This is understood from a point of view that we don't understand, and we only judge it from the appearance. But a person with professional knowledge will observe from many aspects, and he will judge whether a calligraphy work is excellent according to whether it shows art and artistic conception. After thousands of years of development, each art has formed its own complete system, so only those who know can understand the laws.
In fact, it is normal for everyone to have different understandings of the same calligraphy work. Because each of us has our own set of independent thinking ability and a set of brain operation mechanism, we always have different ideas when we look at the same object.