Good ideas come from many sources including slow hunches over time, serendipity, networks of people and information, mistakes, and adapting existing ideas for new uses. The document discusses how ideas evolve gradually and through interaction with others rather than from isolated "eureka moments." Several examples are given of discoveries and inventions that resulted from happy accidents or bringing together different fields of knowledge. Creativity benefits from open exchange of ideas in social settings like coffee houses and salons that historically nurtured intellectual communities in London and Paris.