Having turned my back on propositions, I thought, what am I going to do about this? The area where it really comes up is when you start looking at the contents of consciousness, which is my number one topic. I like to quote Maynard Keynes on this. He was once asked, “Do you think in words or pictures?” to which he responded, “I think in thoughts.” It was a wonderful answer, but also wonderfully uninformative. What the hell’s a thought then? How does it carry information? Is it like a picture? Is it iconic in some way? Does it resemble what it’s about, or is it like a word that refers to what it’s about without resembling it? Are there third, fourth, fifth alternatives? Looking at information in the brain and then trying to trace it back to information in the genes that must be responsible for providing the design of the brain that can then carry information in other senses, you gradually begin to realize that this does tie in with Shannon-Weaver information theory. There’s a way of seeing information as "a difference that makes a difference," to quote Donald MacKay and Bateson.

Ever since then, I’ve been trying to articulate, with the help of Harvard evolutionary biologist David Haig, just what meaning is, what content is, and ultimately, in terms of biological information and physical information, the information of Shannon and Weaver. There’s a chapter in my latest book called “What is Information?” I stand by it, but it’s under revision. I’m already moving beyond it and realizing there’s a better way of tackling some of these issues.

DANIEL C. DENNETT is the Austin B. Fletcher Professor of Philosophy and co-director of the Center for Cognitive Studies at Tufts University. He is the author, most recently, of From Bacteria to Bach and Back: The Evolution of Minds. Daniel C. Dennett's Edge Bio page [2]