Johannes Müller's law of specific nerve energies (LOSNE) states that the mind has access not to objects in the world but only to our nerves. This law implies that the contents of the mind have no qualities in common with environmental objects but serve only as arbitrary signs or markers of those objects. The present article traces the implications of LOSNE for non-physical theories of mind and for modern neural identity theory (that mental events are identical with their neurological representations) (...) and argues that these theories are essentially inconsistent with LOSNE. Teleological behaviorism, a behavioral identity theory of the mind, identifies a person's mind with the correlation over time between that person's overt behavior and environmental objects; this behavioral conception is consistent with a revised form of LOSNE in which the mind is conceived to exist not within the body but at the borderline between the body and the world. (shrink)