First, China's earliest words all appeared in the form of images, recording what he did today and what he saw in his eyes. Intuitive understanding of ancestors. The earliest word is painting, so-called painting and calligraphy are homologous.
Secondly, from the perspective of brushwork, many techniques of painting and calligraphy complement each other. For example, painting bamboo leaves is the "skimming" in calligraphy, as well as "picking" and even "picking". When entering the major of traditional Chinese painting, teachers usually begin to ask students to learn calligraphy.
Third, calligraphy, painting and literature all belong to the art category, and calligraphy and painting need literature to express their contents. Calligraphy and painting is a form of expression, with rough and empty content. No matter how good calligraphy and painting are, they are just painters, not real art.
The above is only a one-sided understanding. I hope my friends will study philology and the history of calligraphy and painting. An in-depth study of philosophy. Let's progress together.