Every new invention changes the world -- in ways both intentional and unexpected. Historian Edward Tenner tells stories that illustrate the under-appreciated gap between our ability to innovate and our ability to foresee the consequences.

Is our obsession with efficiency actually making us less efficient? In this revelatory talk, writer and historian Edward Tenner discusses the promises and dangers of our drive to get things done as quickly as possible -- and suggests seven ways we can use "inspired inefficiency" to be more productive.