In systems thinking, increases in understanding are believed to be obtainable by expanding the systems to be understood, not by reducing them to their elements. Understanding proceeds from the whole to its parts, not from the parts to the whole as knowledge does.
Russell L. AckoffEvery problem interacts with other problems and is therefore part of a set of interrelated problems, a system of problems. I choose to call such a system a mess.
Russell L. AckoffCommon sense … has the very curious property of being more correct retrospectively than prospectively. It seems to me that one of the principal criteria to be applied to successful science is that its results are almost always obvious retrospectively; unfortunately, they seldom are prospectively. Common sense provides a kind of ultimate validation after science has completed its work; it seldom anticipates what science is going to discover.
Russell L. Ackoff