Systems Thinking

Thinking is as important as content. Most traditional textbooks try to work in critical thinking, and that is good, but not enough. Systems thinking is king. Historically, and even today, reductionism has been the mindset of chemists: take something apart, study those parts, and assume the whole is just the sum of those parts. Ain't so. Take your bike apart and, by studying each part, try to tell someone how it worked. You can't. In systems thinking, how those parts work together is just as important as the parts themselves.

Systems have features that none of the parts have. Take water, made of two gases, yet water is nothing like either of them. Or take a piece of wood. If I ask you to describe the many materials in your surroundings, you are sure to name color, size, mass, shape, and texture, and you can do that because of your experiences. But appearance is a property of the system, not of its parts. How to describe it? One way is by uniformity. Is the material uniform regardless of direction? A piece of wood is a good test case. Get your sharp knife and try cutting it in any direction. Is it as easy to cut up as down as crosswise? No. Wood is not uniform. The wood does something none of the fibers does alone.

The opposing habit, reductionism, has a long and honorable history; it has produced real knowledge. But it has limits, and the limits show up whenever the interactions between parts are doing the work. When that is the case, the parts list is silent and the interaction list is where the story lives. In systems thinking, all systems follow the same rules. The problem is that we are still trying to understand what those rules are.

For the macroscopic approach to chemistry, this is not a side detail. It is the shape of the whole enterprise. The Macroscope, a book I return to, does a good job explaining systems thinking and the systemic approach. A macroscope is the instrument that lets us see what is too great and too complex for our eyes, by filtering details and amplifying that which links things together. That is the move: to see chemistry as a network of interacting materials, not as a parts list. The list cannot tell you what the system does. Only the system can.