The odor of formaldehyde, the tasteful thickness of a cut of lamb, the subtle off-white coloring of the walls, the vibratory acceleration of a rollercoaster. Everyday life is filled with subjective qualities of what it is like to experience this or that phenomenon. A quale is not an unfamiliar concept. Qualia (quale being the singular form) are the personally subjective instances of sensation that arise from experience. If you’ve ever had cotton candy at a fair you can recall the experience of marveling at its pink coloring and the warm undulations of sweet taste as it hit your tongue- an ebullient experience. Now, imagine meat flavored cotton candy. The renowned chef Jose Andres actually created foie gras cotton candy. The experience of eating such a dish is unique and you have to experience it to know what it feels like to eat it.
What is it like to be a bat? We know that a bat “sees” by sending out pulses of high-frequency ultrasounds and analyzing the returning echoes. We have a pretty good understanding of how a bat’s sensory system works, but we can never know how it would actually feel like to actually “see” like a bat. We will never know, because we cannot become ordinary bats and think about qualia like we do as humans. You have your own qualia too, as you are reading these words on your computer screen. I will never know how it feels like to be you, seeing what you see with your feelings in your perspective; similarly, you will never know what it feels like to be me, typing out these words. The existence of qualia is widely debated in both the empirical sciences and philosophy. Philosophers disagree on how exactly to define qualia, whether they are representational, and if they are present in animals. These considerations will emerge repeatedly in our investigation of consciousness.