The Evolution of Useful Things A Book by Henry Petroski Here, then, is the central idea: the form of made things is always subject to change in response to their real or perceived shortcomings, their failures to function properly. This principle governs all invention, innovation, ingenuity. Spike and sponShaped and reshapedForm follows failureTheir wrongness is somehow more immediateA small corner of the world of things+23 More The evolution of devices formfunctioninventionprogressfailure
Theory of Change An Essay by Aaron Swartz www.aaronsw.com A theory of change is the opposite of a theory of action — it works backwards from the goal, in concrete steps, to figure out what you can do to achieve it. To develop a theory of change, you need to start at the end and repeatedly ask yourself, “Concretely, how does one achieve that?” changegoals