The main themes of The Geography of Thought are collective agency versus individual freedom and Asian versus Western philosophical and cultural perspectives.

In a nutshell, Nisbett's book explores the differences between Asian and Western cultural and philosophical thought. While Asian cultures prioritize hierarchical social systems focused on mutual collaboration, Western cultures emphasize competitive social systems focused on individual rights and freedoms.

In Asian cultures, community-based social systems promote high levels of solidarity. However, this often comes at the expense of personal freedoms. Essentially, community-based systems rely on the state or government to secure social harmony, while individualist Western cultures see the state as a vehicle to promote the individual's rights.

In his book, Nisbett contrasts the ancient Greek and Chinese cultures. While the Greeks cherished individual liberties, the Chinese valued social harmony. The Greeks were enamored with the idea of individuals exercising their individual talents in the pursuit of excellence. In contrast, the collective imperative dominated over individual freedoms in Chinese culture.

Nisbett also highlights the differences between how the Chinese and Greek cultures categorize the world. The Greeks insisted on categorizing people, objects, animals, and plants according to their taxonomic properties. Meanwhile, the Chinese preferred categorizations based on relationships i.e. how one class related to another, as opposed to how individuals can be categorized.

For example, Western children tend to group objects according to their taxonomic properties. So, they would group animals like cows, sheep, and goats in one category, while grouping grass and other vegetation in a separate category. On the other hand, Chinese children would group the cow and sheep together with the grass. After all, both cows and sheep are grazing animals. The grass is important because it is a means of nourishment for both animals.

As can be seen, Nesbitt clearly highlights the main themes of collective agency versus individual freedom and Asian versus Western philosophical and cultural perspectives in his book.