In addition to your ego barrier, you (and everyone else) also have blind spots—areas where your way of thinking prevents you from seeing things accurately. Just as we all have different ranges for hearing pitch and seeing colors, we have different ranges for seeing and understanding things. We each see things in our own way. For example, some people naturally see big pictures and miss small details while others naturally see details and miss big pictures; some people are linear thinkers while others think laterally, and so on.

Naturally, people can’t appreciate what they can’t see. A person who can’t identify patterns and synthesize doesn’t know what it’s like to see patterns and synthesize any more than a color-blind person knows what it’s like to see color. These differences in how our brains work are much less apparent than the differences in how our bodies work. Color-blind people eventually find out that they are color-blind, whereas most people never see or understand the ways in which their ways of thinking make them blind. To make it even harder, we don’t like to see ourselves or others as having blind spots, even though we all have them. When you point out someone’s psychological weakness, it’s generally about as well received as if you pointed out a physical weakness.

If you’re like most people, you have no clue how other people see things and aren’t good at seeking to understand what they are thinking, because you’re too preoccupied with telling them what you yourself think is correct. In other words, you are closed-minded; you presume too much. This closed-mindedness is terribly costly; it causes you to miss out on all sorts of wonderful possibilities and dangerous threats that other people might be showing you—and it blocks criticism that could be constructive and even lifesaving.

The end result of these two barriers is that parties in disagreements typically remain convinced that they’re right—and often end up angry at each other. This is illogical and leads to suboptimal decision making. After all, when two people reach opposite conclusions, someone must be wrong. Shouldn’t you want to make sure that someone isn’t you?

This failure to benefit from others’ thinking doesn’t just occur when disagreements arise; it occurs when people encounter problems that they are trying to solve. When trying to figure things out, most people spin in their own heads instead of taking in all the wonderful thinking available to them. As a result, they continually run toward what they see and keep crashing into what they are blind to until the crashing leads them to adapt. Those who adapt do so by a) teaching their brains to work in a way that doesn’t come naturally (the creative person learns to become organized through discipline and practice, for instance), b) using compensating mechanisms (such as programmed reminders), and/or c) relying on the help of others who are strong where they are weak.

Differences in thinking can be symbiotic and complementary instead of disruptive. For example, the lateral approach to thinking common among creative people can lead them to be unreliable, while more linear thinkers are often more dependable; some people are more emotional while others are more logical, and so on. None of these individuals would be able to succeed at any kind of complex project without the help of others who have complementary strengths.