“I found myself drawn to biology, with all its frustrating yet fascinating complexities. When I was twelve, I remember reading about axolotls, which are basically a species of salamander that has evolved to remain permanently in the aquatic larval stage. They manage to keep their gills (rather than trading them in for lungs, like salamanders or frogs) by shutting down metamorphosis and becoming sexually mature in the water. I was completely flabbergasted when I read that by simply giving these creatures the “metamorphosis hormone” (thyroid extract) you could make the axolotl revert back into the extinct, land-dwelling, gill-less adult ancestor that it had evolved from. You could go back in time, resurrecting a prehistoric animal that no longer exists anywhere on Earth. I also knew that for some mysterious reason adult salamanders don’t regenerate amputated legs but the tadpoles do. My curiosity took me one step further, to the question of whether an axolotl—which is, after all, an “adult tadpole”—would retain its ability to regenerate a lost leg just as a modern frog tadpole does. And how many other axolotl-like beings exist on Earth, I wondered, that could be restored to their ancestral forms by simply giving them hormones? Could humans—who are after all apes that have evolved to retain many juvenile qualities—be made to revert to an ancestral form, perhaps something resembling Homo erectus, using the appropriate cocktail of hormones? My mind reeled out a stream of questions and speculations, and I was hooked on biology forever. I found mysteries and possibilities everywhere.”

“The law of perceptual problem solving, or peekaboo, should now make more sense. It may have evolved to ensure that the search for visual solutions is inherently pleasurable rather than frustrating, so that you don’t give up too easily.”

“How can a three-pound mass of jelly that you can hold in your palm imagine angels, contemplate the meaning of infinity, and even question its own place in the cosmos? Especially awe inspiring is the fact that any single brain, including yours, is made up of atoms that were forged in the hearts of countless, far-flung stars billions of years ago. These particles drifted for eons and light-years until gravity and change brought them together here, now. These atoms now form a conglomerate- your brain- that can not only ponder the very stars that gave it birth but can also think about its own ability to think and wonder about its own ability to wonder. With the arrival of humans, it has been said, the universe has suddenly become conscious of itself. This, truly, it the greatest mystery of all.”

“The common denominator of all jokes is a path of expectation that is diverted by an unexpected twist necessitating a complete reinterpretation of all the previous facts — the punch-line…Reinterpretation alone is insufficient. The new model must be inconsequential. For example, a portly gentleman walking toward his car slips on a banana peel and falls. If he breaks his head and blood spills out, obviously you are not going to laugh. You are going to rush to the telephone and call an ambulance. But if he simply wipes off the goo from his face, looks around him, and then gets up, you start laughing. The reason is, I suggest, because now you know it’s inconsequential, no real harm has been done. I would argue that laughter is nature’s way of signaling that "it’s a false alarm." Why is this useful from an evolutionary standpoint? I suggest that the rhythmic staccato sound of laughter evolved to inform our kin who share our genes; don’t waste your precious resources on this situation; it’s a false alarm. Laughter is nature’s OK signal.”

“Self-awareness is a trait that not only makes us human but also paradoxically makes us want to be more than merely human. As I said in my BBC Reith Lectures, “Science tells us we are merely beasts, but we don’t feel like that. We feel like angels trapped inside the bodies of beasts, forever craving transcendence”

“The human brain, it has been said, is the most complexly organised structure in the universe and to appreciate this you just have to look at some numbers. The brain is made up of one hundred billion nerve cells or "neurons" which is the basic structural and functional units of the nervous system. Each neuron makes something like a thousand to ten thousand contacts with other neurons and these points of contact are called synapses where exchange of information occurs. And based on this information, someone has calculated that the number of possible permutations and combinations of brain activity, in other words the numbers of brain states, exceeds the number of elementary particles in the known universe.”

“Now I am an axolotl.”