A cross between a notebook and journal, commonplace books were kept by most of history's most renowned luminaries, including the likes of Isaac Newton and Leonardo Da Vinci.
Most recently, the founders of Intel used "patent notebooks" which hold strong similarities to commonplace books, in order to record their discovery / invention of the integrated circuit and microprocessor - two of the most defining technologies of our time.
What Is Commonplacing & Why Is It Important?
Not quite note-taking, not quite scrap-booking, commonplacing would likely be better called the "Intelligent Man's Journal". It's a way to track, discover and indulge in new ideas.
Although there are absolutely no contemporary sources on how to effectively keep a commonplace, the principles continue from the past, whereby you're encouraged to feed your curiosity by investigating new ideas (going to art museums, trips to other countries, reading new books, visiting the opera etc).
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