Al-Sayyid Bedouin Sign Language

10.1 The forbidden experiment Language and culture separate humans from all other species. No human group lacks either, which must mean that both are deeply seated in human nature. What are the essential ingredients of these two most human of attributes? Our central task as linguists is to try to answer this question for language. One strategy for tackling this problem is to trace all existing human languages back to some original and so discover the fundamental properties of language. Nineteenth-century historical linguists tried to do this, with notable success, beginning from William Jones' observation that Sanskrit was so similar to Greek, Latin, Gothic, Celtic, and Persian that they must have descended from a common ancestor. Though remarkably reliable, the methods of historical linguistics are incapable of taking us back more than a few thousand years. In the nineteenth century, when most educated people believed that the world had begun no more than six thousand years before, these limitations presented no barrier to answering the question of the origin of language and historical linguistics flourished. But Charles Lyell, the founder of geology, destroyed all such hope when he argued successfully that the earth must be much older. We now know that the earth is billions of years old, that the human lineage split from the other great apes approximately six million years ago, and that anatomically modern humans have inhabited the earth for at least one hundred thousand years, emerging from Africa to spread across the globe at least fifty thousand years ago (see Dediu, this volume, Chapter 28). All of which means that we will never learn, using conventional historical linguistic methods, what the first human language was like. Another tactic that linguists have advocated is to compare many modern languages. If we can discover what they all share, sometimes called language universals, then this may tell us what the basic structure of human languages is like. But detailed comparison of many languages has revealed