ELI5: Explain Like I'm 5

Thought experiment

A thought experiment is a way of exploring an idea or concept that you can do in your own head. It's like a science experiment, except you don't need any equipment to do it. Instead, you use your brain and imagination to explore a situation. For example, you could think about what it would be like if everyone in the world had the same color eyes. That would be a thought experiment.