Abstract

What does it feel like to be a bat? Is conscious experience of echolocation closer to that of vision or audition? Or, echolocation is non-conscious processing and it doesn’t feel anything? This famous question of bats’ experience, posed by a philosopher Thomas Nagel in 1974, clarifies the difficult nature of the mind-body problem. Why a particular sense, such as vision, has to feel like vision, but not like audition, is puzzling. This is especially so given that any conscious experience is supported by neuronal activity. Activity of a single neuron appears fairly uniform across modalities, and even similar to those for non-conscious processing. Without any explanation on why a particular sense has to feel as the way it does, researchers even cannot approach the question of the bats’ experience. Is there any theory that gives us a hope for such explanation? Currently, probably none, except for one. Integrated Information Theory (IIT), proposed by Tononi in 2004 has a potential to offer a plausible explanation. IIT essentially claims that any system that is composed of causally interacting mechanisms can have conscious experience. And precisely how the system feels like is determined by the way the mechanisms influence each other in a holistic way. In this talk, I will give a brief explanation of the essence of IIT and provide initial empirical partial tests of the theory, proposing a potential scientific pathway to approach bats’ conscious experience. If IIT , or its improved or related versions, is validated enough, it will gain credibility to accept its prediction on rough nature of bats’ experience. If we can gain a sophisticated insight as to whether bats’ experience is closer to vision or audition, it is already a tremendously big step in consciousness science, which is just a first yet critical one, possibly a similar level of the breakthrough in cosmology in precisely estimating the age of the universe.