Where do new ideas come from?

New ideas can happen anywhere, at any time. Some believe that it is some sort of 'Eureka!' moment, but new ideas usually come from prolonged thinking and brainstorming. Most great inventors and scientists in history rarely think up their theory in moments, unless you count Isaac Newton's 'apple on the head' moment of enlightenment. Ideas usually come from experiences coupled with imagination, or problems that are in urgent need of solving. An example of this is Alexander Graham Bell's invention, the telephone. Many people were having trouble with long-distance conversations, having to rely on telegraph or letters. Even though this is usually fine in most circumstances, emergencies posed an urgent problem to the usual time it took for a letter or telegraph to be delivered. This was a problem that needed to be solved , and the telephone became the solution that let others talk simultaneously to one another. Sometimes, ideas come from someone else's thoughts or words, something that sparks one's imagination and in time forms an idea. Other times, the different people would come to the same conclusion and scramble to publish their ideas first, like Charles Darwin and Alfred Russel Wallace. Each came to a similar theory on evolution and while Darwin had come to the conclusion first, he had yet to publish his ideas. This gave way to a scramble for the patent of the theory. All these are ways to come up with new ideas, which are usually revised over and over to become a single, original idea that is both interesting and appealing to humanity, or maybe something that interests you.