The Course of Reason

The Brain: A User’s Manual

December 24, 2013

If you are reading this, then you have a brain. Thus far you’ve achieved great things with your brain, and you should be proud! Right now you are decoding a system of arbitrary symbols that represent phonemes of words in the English language, and that is no trivial task. What else can you do with your brain? It is a good idea to try and figure that out. We don’t know for sure the limits of the brain, but through lots of hard work, we’ve made some progress.


A human brain, like yours. 

A human brain, like yours. 


The brain has a lot of known defects that you should be careful about. For example, if you shake your brain, it won’t work as well. There are certain chemicals that, when introduced to the brain, cause it to function in strange ways. One of the main functions of your brain is to believe things about the world. There is no guarantee that these beliefs are true, so your brain will probably believe a lot of false things, in addition to some true things if you are lucky.

If you are not a fully developed adult human, then your brain is not fully built yet. This can be frustrating. If you are small child, then your brain is mostly focused on learning a natural language, and how to interact with your body. To learn more about your body, see one of the many user’s manuals.

To make things easier for you, your brain has come pre-programmed with some beliefs. Some of these are false. You should try to figure out which ones are false, and correct them. That is something your brain can do. It is called “reasoning”.

The brain can do some things “on its own,” like cause your body to move away from damaging situations. The part of your brain that is “you” doesn’t need to think about this stuff. But reasoning is not something the brain does on its own, so you will have to be involved in this process. If left to its own devices, your brain will form a lot of beliefs without reasoning. For example, for a while you will think your parents know everything, and you will believe what they say unquestioningly. Then, later on, this will reverse, and you will think everything they say is false. Neither of these beliefs is true.

In addition to the above complications, other things with brains, mostly humans, will try to convince your brain to believe one thing or another. Some brains are really good at convincing other brains to believe stuff, but this doesn’t mean they are good at finding true beliefs. In fact, some brains that are good at finding true beliefs are really bad at convincing other brains, depending on the circumstances. A brain might have a perfectly true belief, but this belief might be inconvenient for other brains, so the other brains will ignore the brain with the true belief.

When another brain tries to convince your brain to believe something, you should make sure the other brain can provide good reasoning in support of the belief. There are other ways to convince your brain, like by making threats, or by promising a reward, but these ways don’t provide good support for a belief.

Your brain needs to do something called “sleep”, for several hours a day. We don’t know why, but without entering this sleep state it will eventually stop working. When your brain sleeps, it might do funny things. It will make you think you are seeing and hearing things that aren’t real. Sometimes this experience will be terrifying. Occasionally, some brains might have similar experiences when they are not in a dream state. This problem with your brain concerns the data it receives from your sensory organs. These data are noisy and incomplete, because your sensory organs are quite bad. But also, the connection between your sensory organs and your brain are bad.

Your brain tries to interpret the data as best it can, but it often makes mistakes. Your brain will think it sees and hears things that don’t really exist, ranging from very minor mistakes to very large and important mistakes. These are called hallucinations, or illusions. We apologize for this inconvenience, but you should remember this information because those experiences will have an effect on your brain’s beliefs, usually a bad effect.

Remembering things is another thing your brain can do, but not very well. For example, even though you just read all of the earlier words in this manual, your brain cannot remember them all. This is called forgetting, and your brain will forget a lot of things. But things don’t stop there. Your brain will also remember things that didn’t really happen. Keep these things in mind when other brains are sharing their memories with your brain.

Your brain won’t work forever. When it stops working, you will die. You should usually be careful not to allow your brain to stop working, if you can help it. If you think your brain is about to stop working, you can ask other brains to help. Sometimes other brains can get your brain working again if it only stopped working for a little bit. But after a certain amount of time, it won’t start working again.

We’re not sure what happens when your brain stops working, but this is a very important issue for most brains. A lot of brains care very deeply about beliefs concerning this. Many brains will spend a lot of time and energy trying to convince your brain to believe a certain thing about what happens when it stops working. You should be careful about believing these other brains, though, keeping in mind the things described in this manual. What your brain believes about when it stops working can have a big impact on many of its other beliefs, and the actions it chooses. That’s why it is an important belief, otherwise we would not mention it in this manual.

If you try to picture what happens when your brain stops working, then you are doing something called “imagining”. This is another thing the brain can do. The brain imagines things by inventing interpretations of data that don’t actually exist. This is usually different from hallucination or illusion, because the brain does not usually believe that the things it imagines are real. It is usually a little game you can play with your brain, and some brains like to share the things they imagine with other brains. This is perfectly fine. But sometimes a brain will share something it imagined without mentioning that it was imagined, and this is called “lying”. Sadly, lots of brain lie. If you catch your brain lying, you should apologize to the other brains, and make it clear that you were just sharing things that you imagined.

If you think that your brain is not working as well as it should be, you can go to a doctor for help. A doctor is a person who has spent a lot of time making their brain learn about how the brain and body work, and how they break down. If you want, you can become a doctor by spending a lot of your time and resources learning things about the brain and body, until other doctorized brains recognize your brain as a doctorized brain. They will give you a piece of paper that says you are a doctor.

You can make your brain learn about a lot of things. It is recommended that you make your brain learn about a wide variety of things, and then focus your efforts on something that is particularly pleasing for your brain to learn about. Some brains focus on playing games, others on imagining things, others on learning about specific things. You can have a lot of fun figuring out what you want to do with your brain.



About the Author: Seth Kurtenbach

Seth Kurtenbach's photo
Seth Kurtenbach is pursuing his PhD in computer science at the University of Missouri. His current research focuses on the application of formal logic to questions about knowledge and rationality. He has his Master's degree in philosophy from the University of Missouri, and is growing an epic beard in order to maintain his philosophical powers. You can email Seth at or follow him on Twitter: @SJKur.




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