01 See for example de Bono, E. (2017). Six Thinking Hats. Penguin UK. See also Crawford, R. P. (1968). Direct Creativity with Attribute Listing. Fraser. And see http://www.toyota-global.com (Company → Toyota Traditions → Quality).
02 See Crawford, R. P. (1968). Direct Creativity with Attribute Listing. Fraser.
03 See http://www.toyota-global.com (Company → Toyota Traditions → Quality).
Often, the theme of ideation is too large or abstract to get a grip on. You can use various techniques to limit or split the theme into more manageable chunks, see different aspects of the theme, and produce more diverse ideas.
Various approaches or techniques can be used to split an ideation challenge into smaller subunits. Here are some useful examples: 
- In the Six Thinking Hats exercise by Edward de Bono, participants are encouraged to sequentially adopt different viewpoints by changing hats (blue for managing the big picture, white for information and facts, red for emotions, black for discernment and logic, yellow for optimistic response, green for creativity) and ideate from these.
- “Attribute listing”  takes different attributes (such as physical, social, procedural, or psychological) of a problem or idea and looks at them individually, ideating around each one.
- The “5 Ws + H” technique invites participants to ask themselves six questions (who, where, what, why, when, and how – these questions that have been asked by philosophers since antiquity) and look at variations of the answers to each of those.
- In the “Five Whys” method made famous by Toyota , we look at a problem or fact and ask ourselves “why” five times or more. Each answer can be the starting point for ideation.