Perception Is Subjective: How We Sense Reality

This article is an excerpt from the Shortform book guide to "The Fifth Agreement" by Don Miguel Ruiz. Shortform has the world's best summaries and analyses of books you should be reading.

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What does it mean that perception is subjective? Do we know what’s real?

We don’t sense everything, and what we sense might not be real. In other words, perception is subjective. Authors Miguel Ruiz and Jose Ruiz discuss this point in their book The Fifth Agreement.

Keep reading to learn how perception is subjective.

Perception Is Subjective

In the opening chapters of The Fifth Agreement, the authors (also known as the naguals) invite us to challenge our perception of reality. What we see isn’t all there is, they say, and much of what we do see isn’t objectively real. In other words, perception is subjective. Further, they argue that our knowledge and beliefs are just as subjective as our perception, and that accepting the values and mores of our cultures without doubt restricts our freedom and prevents us from being truly happy. In challenging what we see and believe, the naguals say we can reclaim the power to experience the world we enjoyed as children, free of judgment, self-criticism, and shame.

The authors’ first point is that perception is subjective. The world we perceive through our senses is only a subjective interpretation of a thin slice of what actually exists in the world. They argue that the information our senses give us is heavily filtered and fabricated: Our brains interpret a narrow band of radiation as “color,” the presence of certain particles in large enough numbers as “smells,” and waves of compressed air as “sounds.” Without eyes, ears, and noses—and brains to interpret their signals—colors, smells, and sounds would not exist; in a literal sense, they don’t exist outside of us.

Furthermore, “reality,” the authors explain, isn’t perceived the same way by everyone who experiences it. Some of us are more sensitive to smells, see fewer colors, or can hear at higher frequencies. Plus, other creatures on our planet interpret the same world in very different ways—bats, for example, “see” reality in a way that’s so foreign to us that we can’t accurately imagine it. In short, we can’t assume that we all perceive the same world.

Shortform Commentary: Magenta Doesn’t Exist

As the Ruizes say, the world we experience using our senses isn’t an accurate portrayal of what’s really out there. Perception is subjective. We often take our brains for granted, failing to realize how untrustworthy they are. There are dozens of studies showing how the brain’s hasty processing leads us to see things that aren’t there, come to conclusions that don’t make sense, or ignore important details.

It’s not just that our brains are often too rushed to do a good job; sometimes they just make things up. You may have heard, for example, that the color magenta doesn’t exist. In the image below, you can see the frequencies and wavelengths of each of the visible colors (colors generally correspond to a particular wavelength of radiation). Magenta isn’t there.

The reason we see magenta in our daily lives is because our brains are used to averaging the colors we see into a blend. Green and red, when seen together, become yellow because yellow is the average wavelength between green and red. When red and purple appear together, we should see green—it’s the average wavelength between the two. But it doesn’t “make sense” for red and purple to mix into green, so our brains substitute “magenta.” Essentially, we only see magenta because “it looks right”—not because it reflects reality.