Mary's Room

Hey, today is #PhilosophyFriday ๐Ÿค”!

How about discussing some philosophical aspects of Computer Science?

Today I want to talk about Mary's Room ๐Ÿ‘‡

This is a very interesting thought experiment that is related to the nature of knowledge and the difference between knowing something and knowing about something.

There are many variants of the experiment, but my favorite one goes like this ๐Ÿงต:

Mary is a renowned neuroscientist who has studied everything there is to study about human vision. She understands every little bit of science regarding how light enters the eye, how it is received, and how it is processed in the brain... ๐Ÿ‘‡

Furthermore, Mary understands perfectly all the physics of color, she can say exactly which portion of the spectrum is called "red", "green", "blue", or any other color you can mention... ๐Ÿ‘‡

Even more, Mary has interviewed thousands of people, scanned their brains, measured their retinas. She understands all the physical phenomena that happen when everyone else sees a color... ๐Ÿ‘‡

But... Mary is absolutely color blinded. She has a rare genetic disease that makes her see everything in monochrome. So, being the top researcher in the whole world regarding the human experience of color, she has never "experienced" color herself... ๐Ÿ‘‡

One day, a miracle of science allows Mary to regain the ability to see color, in all its glory. And for the first time in her life, Mary looks up, and she experiences the blue sky โ˜๏ธ!

โ“ At this point, does Mary gain any new knowledge that she didn't previously have?

Think carefully. There is no right or wrong answer, just let me know at this point what do believe and, more importantly, why.

Before you leave, I have a few more comments to make ๐Ÿ‘‡

๐Ÿ…ฐ๏ธ If you think Mary doesn't learn anything new, then you believe in "physicalism": the notion that the physical world is everything there is. In particular, all human experience is ultimately caused by physics and there is nothing above it.

๐Ÿ…ฑ๏ธ If you think there is something new she attained after experiencing color, that she couldn't possibly have known before, then you believe in the existence of "qualia": subjective experiences that cannot be explained or understood without experiencing them.

๐Ÿค” Most philosophers and scientists (including computer scientists) describe themselves as physicalists or at least materialists. However, it is very hard to explain what I experience as "being red" or "being cold" or "being painful", without having you experience it.

"But what does this have to do with computers", you ask?

Well, if qualia exist, then it is very hard to believe in strong artificial intelligence. Since computers will not experience the world the way we do, how will you know that they know what "pain" or "love" is?

And that's it.

Now I just want to leave the discussion open. There is no right or wrong answer here since philosophers themselves don't even agree (this is hardly surprising, though, put N philosophers in a room and you will have N+1 opinions ๐Ÿ˜†).

If you want to read this in a more "classic" format or bookmark it for later, check it out here:

๐Ÿ—จ๏ธ You can see this tweetstorm as originally posted in this Twitter thread.