Are you one or many? Most people call themselves I not we, but if “I” refers to the body, it is a collective of cells that constantly die and are replaced. Skin loses about a million cells a day and it is just one organ. Red blood cells live maybe four months, white blood cells a year or so, skin cells a few weeks and colon cells only a few days. Where is the “I” in a bunch of cells that come and go? Even if nerves last a lifetime, that I am my nerves leads one biologist to conclude:
“The Astonishing Hypothesis is that ‘You’, your joys and your sorrows, your memories and your ambitions, your sense of identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. As Lewis Carroll’s Alice might have phrased it: ‘You’re nothing but a pack of neurons’.” (Crick, 1995)
If this is true, is “I” in reality “We”? Is science telling us that “I” is a medieval error, like the idea that the earth is flat? If so, one should say “We did this” instead of I did it. If you don’t want to call yourself “We”, then welcome to the hard problem of consciousness (Chalmers, 1996), that we experience life as a single “I” even though we are physically a collective.
Neurons respond to one light frequency as “red” and another as “blue” but why is red this experience and blue that one? Nothing in neuroscience requires processing different light frequencies to give experiences, so what causes red and blue qualia? The hard problem is that sensory input creates an experience as well as a response.
Imagine a scientist who knew all the facts there are to know about blue from a monochrome screen, like how neurons analyze blue light frequencies (Jackson, 1982). If she then goes outside to see blue for the first time, it’s a new experience, so what does she know now that she didn’t before? The hard problem is that the facts of blueness don’t explain the experience of seeing blue.
The Islamic scientist Avicenna proposed a thought experiment: a man floating in a void with no body sensations at all has no awareness of his arms, legs, heart or any other body part but still knows he exists. The first knowledge of the floating man is I am, as even if all thoughts stop, the observer remains. The hard problem is that an observer exists even if nothing is being observed.
We know we are conscious and so see a world of conscious beings like us and unconscious things, but where is the line between them? If people are conscious, are dogs? What about insects or plants? If I am conscious, is the baby, fetus or single cell I came from also conscious? If not, the problem again is where to draw the line?
Dividing the world into beings and things gives an explanatory gap between the matter we are made of and our experience of it (Levine, 1983). I observe a room of matter but as part of the room, I am also matter so what applies to it applies to me as well. Am I also a thing? Conway’s free will theorem is that if the same rules apply to everything, either everything is conscious or nothing is (Conway & Koch, 2006). If we are conscious, so is matter but if matter isn’t, then neither are we. It is illogical to claim that we are conscious but the universe we came from isn’t. The hard problem is that no matter property leads us to expect the observer experience we report.
After centuries of talk, the hard problem is no easier today than it ever was:
“The question of how matter gives rise to felt experience is one of the most vexing problems we know of.”(Brooks, 2020)
It is impossible to ignore the fact that we experience life in a body made of matter.