“The map is not the territory” is a metaphor that demonstrates that your perception of something is not the same as the reality. For example, how you view your relationship with someone else is not exactly the same as how that person views their relationship with you. Another example would be how physical objects are different from how you see them. You could see an apple, but you don’t see all the individual cells, molecules, protons, and quarks that compose that apple. Every level of perception is an abstraction. How you feel about something is based on your own perception.
The map is not the territory, but you comprehend everything as a map. You can’t perceive actual reality, everything is understood and communicated through analogy. There are two ways to think of this.
The first is that two people could have the same map for two different territories. They could superficially describe something in the same terms, but could have completely different underlying beliefs. For example, all Christians believe that the Bible is the Word of God. However, over time, even though they all believed in the Bible, different sects had different interpretations and the religion gradually branched into different churches.
The second is that two people could have different maps for the same territory. Example, many of the underlying lessons of Christianity and Buddhism are the same. But some people may be more open to one map than the other. The differences between the maps may be superficial to the underlying truth. It’s a different road leading to the same conclusion. It’s coming to the truth in two different ways.
The more you’re focused on your map and not open to other people’s maps, the more likely you are to disagree. Since you can’t actually see reality, understanding and communication is through analogy, which is the map. You need to take the effort to understand someone else’s map in order to understand them. It’s empathy.