This is a thinking exercise that helps you get more information before you make a judgement. It allows you to scan for what you know in different directions.
When considering an issue or statement:
make three individual lists of the Positive, Minus and Interesting aspects
spend only about 1 minute "looking" in each direction
leave your emotions out of it
This is not a categorization technique. Don't make a list and then categorize the items. This is meant to focus your attention in at least three different directions.
The interesting category is very important. It allows you to explore ideas outside the normal judging system.
Cars should be banned from city center.
Portland State should require that all new construction be "green" buildings.
Oregon should build toll roads.