Why do scientists think that the voynich manuscript has six chapters or sections?

Although the Voynich Manuscript is not divided into chapters or even sections, scholars believe the book is divided into six parts: herbal, astronomical, biological, cosmological, pharmaceutical and prescriptions. The manuscript may be of a magical or scientific nature.

Explanation:

Illustrations are conventionally used to divide most manuscripts into six different sections because the text itself cannot be read and no one has ever been able to read it, and the illustrations present six different topics, and so the book is thought to be divided into 6 chapters: botany, astronomical charts, naked female figures in tubs, cosmos, use of plants, and unexplored text that it cosidered to represent food recipes.