A lot of good ideas are actually bad ideas because, since they sound good, everybody's already doing them.

It's not even known how many kinds of cells there are in the brain. If you were looking for a periodic table of the brain, there is no such thing. I really like to think of the brain as a computer.

I think the definition will change as we learn more, but my working definition of solving the brain is: one, we can model, maybe in a computer, the processes that generate things like thoughts and feelings, and two, we can understand how to cure brain disorders, like Alzheimer's and epilepsy. Those are my two driving goals. One is more human-condition oriented, and one more clinical.

Suppose there are some things that we don't understand about the universe, but if you understand human intelligence and you understand the gaps in our abilities to think about things, maybe we can engineer in a computer more advanced intelligences that can help augment our ability to think.

For the last century of neuroscience, lots of people have tried to control neurons using all sorts of different technologies - pharmacology (drugs), electrical pulses, and so on. But none of these technologies are precise. With optogenetics, we can aim light at a single cell, or a set of cells, and turn just that set of cells on or off.

The brain is really hard to see. The whole thing is very large - the human brain is several pounds in weight - but the connections between brain cells, known as synapses, are really tiny. They're nanoscale in dimension. So if you want to see how the cells of the brain are connected in networks, you have to see those connections, those synapses.

When I'm talking to somebody, I'll put a piece of paper on the table and I'll write what I call a conversation summary - notes about the conversation on the piece of paper. At the end of the conversation, I'll take a picture on my phone and give the other person the original piece of paper.