Introduction
Ever since Charles Darwin published The Origin of Species, biologists have increasingly seen human beings as just one kind of animal. Darwin's theory of evolution claims that we are descended from other, earlier kinds of animals by natural selection.
Biologists are not surprised, therefore, that our respiration, nutrition, and reproduction are typically mammalian; and that our cells look very like the cells of other animals, with their nuclei and cytoplasm and the multiplicity of organelles that we can see under an electron-microscope. But even a biologist would have to agree that we have some important distinctive traits, and one of the most important is that we use language, to speak, to write, and, some would say, to think. So far as we know, we are the only animals, from the amoeba to the elephant, that naturally use language. Furthermore, many of the other distinguishing features of our species—our social organization, our arts and crafts and sciences—are inconceivable without language. Even if other animals do have languages, what they have done with them seems very limited by comparison. Imagine trying to coordinate a bank or an art gallery or an experiment in chemistry without being able to understand, speak, read, or write a word.Human beings have been using language for at least a hundred thousand years, and most of us learned a language easily and naturally when we were very young. In Chapter 1 I mentioned how easily we have come to take computers, which are relatively new on the human scene, for granted; how much easier it is for us to take language for granted, along with all the distinctively human activities that it makes possible. But actually, what we can do with language is fairly remarkable. For example, we can put together strings of sounds or written symbols that connect us over unimaginable distances of space and time with other places and periods.
Suppose I ask, “Are there creatures with consciousness on the other side of the galaxy?” Then I am in some sense connected, by those words, over hundreds of light-years with a place that I couldn't literally get to in many lifetimes of travel in a spaceship. If you speak of “when life on Earth began,” you are talking about something that happened several thousand million years ago. And we make these connections simply by making sounds or writing letters on a piece of paper or typing them onto a computer. How does it come about that these words in our language—English—can be used to connect us to things both far away and near?We can also use language to talk about things that we will never know about. Thus, we can say: “I wonder what Caesar's last thoughts were.” But we'll never know the answer. Of course, we think we know what his last words were: “Et tu, Brute.” And that raises another fascinating set of puzzles. For why is it that in his language, Latin, the way to say “You too, Brutus” is to say those famous Roman words? And how come different sounds and signs are used in other languages to make the same connections?
3.2