Hilary Putnam proposed a thought experiment called “Alternate Earth” that was, apparently, intended to suggest that the definitions of some language terms lodge in the real world, and not in the mind — not as merely objects of human intention. I don’t intend to repeat his alternate earth scenario here, only to suggest why such theories are difficult to credit.
Let’s take the typical example of gold. To fully understand the nature of gold, the argument goes, you have to do a scientific examination of the material. It is first reduced to a chemical element. It has a slot in the periodic table. This reduction leads to the definition of gold as one specific type of atom, with so many protons and so many neutrons in its nucleus. Gold, then, is an atom with a certain atomic number and a certain atomic weight. And from this understanding, it follows that the full definition of gold is to be found not by looking in a dictionary, but by examining the material itself.
The problem with this view is really very simple: How does the scientist choose a sample to study, if he doesn’t already know what gold is?
Obviously it’s a recursive problem. The ordinary knowledge of gold lacks scientific detail, which can only be acquired through careful scientific study of a real sample. Yet without that ordinary knowledge, it’s impossible to select an appropriate sample to study. In fact, there’s no way out. The first scientist to study gold on a chemical and atomic level had to start with his ordinary knowledge of what gold is. From there, the scientific research provided an elaboration, but it was not the effective defintion. It was only an explanation.
Thus the conclusion is that language is defined mentally and intentionally, and not by any external, objective entities.
