All programming languages are not created equal. Some clearly excel at solving different problems. There are languages that are great for scalability and others that are great for proving correctness. But what about one that that will make you smarter? To look for this answer, I am going to turn to a different language, our human language, and research from the field of linguistics and cognitive development.

A new language is born

Up until the late 1970s, there was no school for the deaf In Nicaragua. Being deaf before then meant only developing crude signs with your family and friends. Beyond that there was nothing. Finally, the wife of the dictator set up a special school for them. This was the first time that the children were brought together in one place rather than being scattered about. For most of them, it was the first time that they had ever met another deaf person. There were about fifty kids in that first class and they came together with fifty different ways of communication with crude gestures. But after awhile, something amazing happened. They started to converge into a common system - a language was born. For scientists, this was an incredible opportunity to watch a new language develop. One of the fascinating insights had to do with how the this sign language evolved over the generations of children entering the school. One in particular, was a study about how words in a language can actually increase your cognitive capacity and make people smarter.

The study involved a test that was performed on different generations of students from the school, including the very first students who were now grown and younger children. A comic strip shown to the participants. In it there are two brothers. The big brother is playing with the train and the little brother wants the play with it. The big brother puts it under the bed and goes out to the kitchen to get a sandwich. While the big brother is gone, the little brother takes out the train and hides it in the toy box. The question for the test subjects is, “When the big brother comes back, where is he going to look for the train?”

Thinking about thinking

For most kids over the age of five, the answer will be that the big brother will look under the bed because he doesn’t know that it has been moved to the toy box. The interesting thing was that the first generation of kids that went through the school, now thirty five years old, failed this simple test. The younger ones all passed. What was going on?

To find out, the scientists looked a differences in the language over the generations and found that the older signers lacked words for the concept of thinking. The earlier generation just had one word for think, while the later generations had evolved ten or twelve. Words that expressed concepts like understand and believe. It seems that having words gave them access to a concept that otherwise would have been really hard to think about. It increased their cognitive capacity. It enabled them to think about thinking.

Thinking about programming programs

Programming languages allow us to translate our human thoughts and instructions to machines. We have words to express simple concepts like adding two numbers together with + or finding how many elements are in a list with count, but what about harder concepts that are more difficult to access? Is there an analogy to having words to think about thinking that some programming languages have that others don’t? I believe there is. It’s having a way to think about a program programming itself with self modifying code or macros.

In Clojure, macros are way to do meta-programming. This involves ability to treat the program as data, allowing a program to modify another program - even its own. It gives Clojure the capability to implement language features, make code more concise, and encapsulate patterns and repetitive code. It is a powerful feature and more to the point of our current line of inquiry, it is a pretty friggin difficult concept to grok. In fact, before I was exposed to a language that had macros in it, I doubt that I would have been able to think about it. For the sake of argument, let’s go back to the comic strip story with the two brothers. But this time, the train is a function and the little brother uses a macro on it when the big brother gets a snack in the kitchen. What does the big brother expect the result of the program to be when he gets back in the room. Prior to my exposure to Clojure and macros, I am sure I would have failed the test.


So yes, I do think that a programming language can increase your cognitive capacity and make you smarter. I certainly feel that my exposure had expanded my world and given me access to programming concepts that I did not have with my other programming experience. I also feel certain that there are other languages out there, both existing and yet to be invented, that have words to express concepts that am not even aware of. Languages that are just waiting for me to expand my horizons.

And that certainty makes me incredibly happy and grateful to be a programmer.

Listen to whole fascinating story of Ann Senghas studying sign language that born in Nicaragua on Radiolab