Abstract
Birch, Ginsburg, and Jablonka, in an article in this issue of Biology and Philosophy, provided a much-needed condensation of their well-reasoned theory of Unlimited Associative Learning (UAL). This theory compellingly identifies the conscious animals (vertebrates, arthropods, and cephalopod molluscs) and the time when the evolutionary transition to consciousness was completed (Cambrian Period). The authors convincingly explained their use of UAL as a "transition marker," identified two more features by which UAL can be recognized, showed how UAL's learning features relate to consciousness, and how investigating consciousness is analogous to investigating life. My constructive criticisms are that I wish they had taken a stand on which organisms and entities are not conscious, and I feel they made too many predictions by which to test the UAL theory. That is, some of the proposed tests are unnecessary because parts of UAL are already supported by enough evidence, and other proposed tests are so ambitious as to be nearly impossible to complete. Finally, UAL has a major, detailed, sub-hypothesis that says such learning led to stress and to the evolution of mechanisms to cope with this stress; but this idea is speculative and requires the most basic testing to judge whether it could be valid.