Science Magazine has an interesting article about a man who can read letters but not numbers. This might sound freakish but anomalies like these have helped scientists understand human mind and human brain much better.
Few hundred years ago no one knew what “caused” a mind. Some people thought mind is an extension of soul and it exists separately from body where as some theorized that it could be result of “heart” and some thought it was brain that caused the existence of mind.
One of the exercises philosophers would do is to ask people “Are you still you, if I cut off your arm?” the answer is Yes. Then the philosopher replaces arm with other organs and ask the same question. This exercise reveals that human notion of
self is not related to any organ but something invisible such as heart or brain.
But when people suffered brain injuries it totally changed their personality. Introverts became extroverts. Stoics became short tempered and so on. It provided key evidence that it was the brain that made people what they are but exactly how brain functions remains a large mystery as we continue to discover more fascinating aspects of the brain.
It was observed for example that parts of brains that are responsible for processing visual images obtained through eyes are capable to retraining themselves to process the environment using sounds if the person goes blind. A particular teenager in San Fransisco who was blind could easily “see” things using a bat like echo-location.
This science magazine article talks about a man who over time lost his ability to read numbers. He was suffering from a disease where he was losing brain cells. Anomalies like these will teach scientists which parts of brains are responsible for processing numbers. This perhaps also tells us that brain understands numbers fundamentally differently than letters and numbers are not “other characters”.