The Six Tools for Thinking

1. So Far As I Know.
1. Only God knows all; no one knows all about anything,
2. No one sees things from all points of view.
3. One overlooked fact can make a big difference.
4. We should hear both sides before making up our minds.
2. Up To A Point.
1. Think in terms of degrees, there are many steps between the extremes.
2. The difference between a good idea and a bad idea is often a matter of degree.
3. There is no such thing as 100% this or that, they do not exist.
4. Beware of the point at which a little more may make more than all before.
3. To Me.
1. The way we feel about things depends on our own particular heredity, training, experience, and personal interests. Each of us has his own particular brand of mental one-sidedness.
4. The What Index.
1. No two things in this world are identical in all respects. We frequently make mistakes by assuming that all things called by the same name will act the same.
5. The When Index.
1. We live in a process world in which all things are changing. The facts of yesterday may be the fictions of today.
6. The Where Index.
1. Any particular person or things may act differently when put in new circumstances. Nothing exists in isolation; everything is affected by surrouding conditions.

Source: How to Develop Your Thinking Ability (1979) by Kenneth S. Keyes, Jr.