Think what you will of Donald Rumsfeld, former U.S. secretary of state under George W. Bush, but his comment in 2002 (about weapons of mass destruction in Iraq) remains one of the most memorable of modern times: "Reports that say that something hasn't happened are always interesting to me because, as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say, we know there are some things we do not know. But there are also unknown unknowns—the ones we don't know we don't know."
Rumsfeld didn't coin the phrase—it was used by NASA and others in the 1970s and 1980s to talk about assessing the risks in aerospace and uranium mining—and it serves to remind us not only that we don't know everything, but that how we perceive our ignorance is colored by our expectations, biases and prejudice.
Similarly, applying information technology in a connected world is explosively increasing our ability to collect and analyze data. But will we be willing and able to use it effectively? I can't remember how many times I've analyzed a process or quality problem, even using design of experiments methods, and ended up chasing my tail because it looked like one or another set of theories appeared to be supported when, in fact, the results were confounded by factors I hadn't thought of, or wasn't aware of, or was kept in the dark about.