According to the Ancient Greek historian Herodotus, the Egyptian pharaoh Psammetichus I performed what was effectively the world's fist recorded psychological experiment. The Psamtik experiment, as it became known, was an attempt to discover whether human beings have an innate capacity for speech. As part of the experiment, the pharaoh ordered two infants to be brought up in a remote place by a shepherd, who was forbidden to speak in their presence. After two years, the children began to speak, and it was discovered that the word they most often used was "beccos," the Phrygian word for bread. To the pharaoh this indicated that human beings had an innate capacity for speech.
However, the experiment was a failure in that its outcome challenged the pharaoh's belief in the Egyptians' cultural superiority. The two boys had, after all, uttered the Phrygian—not the Egyptian—word for bread, indicating that the Phrygians—not the Egyptians—were the older civilization. Nevertheless, the Psamtik experiment was important in that it raised the question of whether or not it was possible to determine that the capacity for language was somehow hard-wired into the human brain.
The debate continues to this day, and the rival schools of thought can—very crudely—be categorized as those who hold that humans are born with a capacity for language and those who argue instead that language is acquired as part of humans' engagement with their social and cultural environment.