If you are breathing, you are thinking. And if you are thinking, you are thinking of all kids of things, and during the day, you’ll have an idea, or a thought. The conversation in your head might sound something like, “I wish someone would invent something that would …” (and then you describe the invention) or, “I bet this would work better if I …” or maybe a funny thought floats through (ahem on myself) and you say, “Oh! This would make a great cartoon!”
Then you continue what you are doing and the idea passes through your brain and out the window.