I have always been fascinated by how things work. As a child, I would follow my father around the yard, helping him with various projects. How, I wondered, did the load in the wheelbarrow always balance? Why could I move a big rock with a crowbar, but not without? How does cement dry underwater?

It is hardly surprising that when I came of age, I followed in my father’s footsteps once more, this time to engineering school. Here I learned the precise formulae that govern the forces of nature. Boring to some, for me these axioms held a special magic, because understanding them conferred great power—the power to harness the forces of nature for the works of man.

I have strayed from my professional roots. Over the past decade at McKinsey, I have helped clients design and execute major change programs, and led research projects on frontline change, operational improvement, and company-wide transformation. I have borrowed many good ideas from the literature on personal and organizational change. Often, however, it has left me wondering how change really works.

I am a mechanical engineer. We mechanical engineers tease our civil engineering colleagues that they only have to figure out how to...