The ancient Egyptians believed the brain's primary function was to produce mucus, which is why they discarded it during mummification while carefully preserving the heart.
Ancient Egyptians Threw Away the Brain as Worthless
When ancient Egyptian embalmers prepared a body for the afterlife, they meticulously preserved the liver, lungs, stomach, and intestines in sacred canopic jars. The heart stayed in the chest—it was far too important to remove. But the brain? They scrambled it with a hook, drained it through the nose, and threw it in the garbage.
To the Egyptians, that grayish mass inside your skull was basically a mucus factory. Nothing more.
The Heart Was Everything
Egyptian medicine and religion placed the heart at the center of human existence. They believed it was the seat of intelligence, emotion, memory, and the soul itself. The famous Book of the Dead describes the heart being weighed against the feather of Ma'at in the afterlife—if your heart was heavy with sin, a demon would devour it.
The brain didn't even make the guest list for the afterlife.
How We Know This
The Edwin Smith Papyrus, dating to around 1600 BCE, is one of the oldest medical texts ever discovered. It describes brain injuries and their effects on the body with surprising accuracy—the Egyptians clearly observed that head trauma could cause paralysis or speech problems.
But here's the strange part: even after documenting these observations, they still concluded the brain was unimportant. They saw the evidence and shrugged it off.
The papyrus doesn't even have a word for "brain" as an organ. It refers to the "marrow of the skull."
The Mummification Process
During mummification, embalmers would:
- Insert a long bronze hook through the nostril
- Scramble the brain tissue until it liquefied
- Tip the body forward to drain the contents
- Discard everything that came out
Meanwhile, they'd spend days carefully treating the heart with natron salts and wrapping it in linen. The contrast couldn't be more stark.
They Weren't Entirely Wrong
Here's the thing—the brain does have a connection to mucus production. The pituitary gland sits at the base of the brain, and cerebrospinal fluid does drain into the nasal passages. Ancient Egyptians may have observed this drainage and drawn a logical (if incorrect) conclusion.
They were excellent observers but sometimes terrible interpreters.
It would take another thousand years before Greek physicians like Hippocrates began arguing that the brain, not the heart, was the seat of consciousness. Even then, Aristotle disagreed and sided with the heart theory.
The debate continued for centuries. The Egyptians just happened to pick the wrong side—and threw away the evidence.
