Eli5: Computers can calculate based on instructions. But how do you teach computers what does it mean to add something, multiply, divide, or perform any other operation?

Question

Edit: Most of the answers here are wonderful and spot on.

For those who interpreted it differently due to my incorrect and brief phrasing, by ‘teaching’ I meant how does the computer get to know what it has to do when we want it to perform arithmetic operations (upon seeing the operators)?

And how does it do it? Like how does it ‘add’ stuff the same way humans do and give results which make sense to us mathematically? What exactly is going on inside?

Thanks for all the helpful explanations on programming, switches, circuits, logic gates, and the links!

In: 583

Answer 1

That really comes down to philosophy, not science. Computers are nothing more than machines with lots of parts. With the arrival of machine learning projects like ChatGPT, they can do some things well enough that they can even fool us into thinking they were done by a human, like writing emails. However, with current AI it is still pretty clear to me that the AI doesn’t really understand what it’s doing. The guiding principle that makes large language models like ChatGPT work is nothing more than pattern recognition. They’re just doing a very advanced version of what your phone does when it suggests to you the next word to type in a sentence. You can tell this in practice by asking ChatGPT to do some basic arithmetic; half of the time it will get the answer right, and half of the time it will give you a wrong answer and be just as certain about it. That’s not because it made an error in calculation, it just didn’t have enough data on that particular math problem or problem like it to guess the right answer.

In the future though, we could imagine an AI that really does form mental models of whatever is learning about and is able to answer essentially any question a human could answer after having learned a topic. So, the question then becomes, does that count as understanding? They also brings up the question of what’s the difference between a machine and a sentient being; if a computer can think and talk in a perfect imitation of a human, is the computer sentient? Or are we just machines? Really crazy stuff to think about.