When my nephew Benjamin was almost two, I bought him a safari picture book. We would spend time together identifying the different objects on each page; I would ask him where the car was on the page, and he would point to it, or where the tree was, and he would point to that. However the first time I asked him “where’s a zebra?” he was stumped. He sat looking straight at one, but instead pointed hopefully to the lion, the hippo, then the gazelle. Finally I pointed out the black and white striped animal and said “that’s a zebra.” He repeated the name thoughtfully, and we went on from there.
The next year Benjamin was enjoying discovering hidden things. Remembering the book I pulled it off his bookshelf, but this time I slyly covered the zebra’s head with my thumb so that only its body and legs were visible. “Where’s the zebra?” I asked. Benjamin couldn’t find it until I moved my hand. “The zebra came!” he said with delight. And so it had.
When Benjamin was nine and I was visiting again, I got out the book, and as a sort of in-joke with him (for even then he had an excellent sense of humor) I opened it up to the zebra page and asked the old question:
“Hey Benjamin, how many zebras are on this page?”
“None,” he said, to my surprise.
What do you mean?” I asked.
“Those are just drawings,” he explained. “Real zebras are alive and three dimensional.” And so they were.
Well, Benjamin is seventeen now, and he recently came to visit my wife and me in New York. Our son Teo is young, and wanted to go to the zoo, so the four of us went to the Bronx to see the animals. When we got to the zebra exhibit I nudged Benjamin for old time’s sake.
“Hey,” I said, “there’s your zebras.”
Benjamin looked at the black and white animals eating their grain and flicking their tails and nuzzling their babies for a moment, and then turned to me. “Where?” he asked.
“Over there,” I said, pointing at the zebras.
“No,” he said, gently grasping my outstretched arm, bending it at the elbow, and placing my finger in my ear. “The zebras are in there,” he said with a smile.
Teo, watching intently, began to laugh. “Zebras in daddy’s ear!” he shouted for all the world to hear. And so they were.
Now on the surface this may seem simply to be a cute story about the process of growing up. But it is much more. In its depths it points to what is perhaps the most vexing question in the philosophy of science, and perhaps the most serious practical problem in all of science:
Is there such a thing as pure observation?
The empirical dream is to answer this question “yes.” In many cases it is a dream that empiricists believe, quite poignantly, has come true. The dream is that a zebra is a zebra, and that red is red, and an apple is an apple, and a group a group, a cell a cell, life life, and brain brain. They want there to “objectively be” what metaphysicians call a “mind-independent world” out there. And they want two things from this world. First, they want it to exist “in and of itself,” and “from its own side,” and to be “really real,” and to “not depend on being observed in order to exist.” Second, they want to be able to know about this world “exactly as it is.” They do not want to have to monkey around with relativism, subjectivity, and consciousness. They do not want to have to talk about meaning and interpretation. They want to simply “see” the world “as it is.” To geek-out for a second by using two words from Kant, one of which is famous and one of which is not, they want the phenomena that appear in their minds to be identical to the noumenal world. They don’t care that Kant and Hume and Quine and Aristotle and Plato couldn’t figure out how this could happen, or that more broadly they are taking the fundamental distinction of metaphysics – that between appearance and reality – and collapsing it. They don’t care that their decision to say “appearance is reality” has never, and can never (we think) be shown to be true – or that, worse, we think this is almost certainly false.
No – this is their dream. And they do not want it fucked with.
Now there are two ways in which empiricists traditionally want to find out about reality. The first is through observation, which refers to the use of the five senses. The second is through detection, which refers to the use of machines – like electron microscopes and the hubble telescope – to see the unobservable. Personally I find the distinction between observation and detection useless. I wear glasses, for example – so do I detect or observe my son in the morning? So I will use the word “observation” to refer to both.
In the empirical dream, you can observe a zebra without any prior understanding of zebras. The zebra is “out there” in the world, not “in here” in your head. Moreover, where empiricists might be willing to admit that interpretation is involved in understanding the meaning of the Bible, or reading the tax law on authorized deductions, and might be willing to allow a little wiggle room to kindergardeners in the identification of zebras, they tend to be adamant that scientific objects – genes and hadrons and background microwave radiation and black holes and statistics – are really, truly “out there” in the world.
But the truth is that most scientists only believe this is practice. As they go about their daily business, they assume there is a world out there that can be known. In theory, however, neuroscientists especially know that the empirical dream is over. The dream that there really is such a thing as ‘raw’ sensation – the prick of a pin beneath our feet, the taste of an apple, the color red, the sound of running water, the smell of pancakes – is just that. A dream. We now know that “cognitive” regions, such as the prefrontal cortex, “backproject” to sensory regions and amplify some features of the world while dampening others. What appears in consciousness is not what is “really there” but rather what is “really important” – or rather, what has been over evolutionary history. Which is to say, through the lens of sex, or reward, or history, everything a nervous system knows is interpreted.
Of course, every child knows this too. If we are concentrating on crossing the street we will not feel a pinprick; if we have just had a chocolate bar an apple will be tart, but if we have been eating bland oatmeal all morning the apple will taste sweet; at dusk the color red will look brown, and so on. No sense observation is ever pure: everything is contextualized by our nervous system. Every fact is interpreted in the light of some other fact, until a web of interrelationship and dependency emerges. Soon it emerges that there is no resting place. There is no raw, unimpeachable, unchangeable fact on which we may plant the flag of inference or, even, deduction. There is no place to start. There is no place to end. Nothing is itself. Everything is going on.
Which is to say, Benjamin was right. There is no such thing as a zebra.