Who was Ibn Sina?

0:00 Welcome to Philosophy is not boring by Kidopoly.com. I'm Mira. And I'm Finn. If you haven't already, tap follow wherever you're listening so you never miss an episode.

0:13 Hey Mira, have you ever tried to feel absolutely nothing? Like completely shutting off your body?

0:20 What do you mean? Like meditating or sitting really, really still in the quiet room?

0:26 Yeah, I tried it the other day. I closed my eyes as tight as I could, and I plugged my ears so I couldn't hear the traffic outside. I tried to just be a brain, floating in the dark. Did it work? Could you escape your body? Not at all. Even in the quietest room, you can hear your own heartbeat in your ears.

0:49 I could feel my toes squished inside my shoes and the chair pushing against my legs.

0:55 It is basically impossible to escape your own body. We are always feeling our physical selves, all day, every day.

1:03 Exactly. But today, we are going to ask a wild, brain-bending question about that.

1:10 What if you couldn't feel your body at all? Would you still know that you exist?

1:15 Okay, so if we couldn't feel our bodies, what would be left of us? Would we even be people anymore? It's a massive question.

1:24 When you think about it, almost everything we know about the world comes from our five physical senses, right? Seeing, hearing, touching, tasting, and smelling.

1:36 Right, so without those senses bringing information in, would we even have a mind? Or would our brains just be completely blank, like a computer that's turned off?

1:47 To figure that out, we have to travel back in time. Not just a little bit, but about a thousand years, to the early 1000s.

1:56 Whoa, that's a really long time ago. Where are we going?

2:00 To the Islamic Golden Age, to meet a Persian doctor, scientist, and philosopher named Ibn Sina.

2:08 A doctor and a philosopher? He must have been a pretty busy guy.

2:13 He was brilliant. In Europe, he was actually known as Avicenna. He wrote a huge medical encyclopedia called The Canon of Medicine that was so good, doctors all over the world used it for hundreds of years.

2:28 So he knew basically everything there was to know about the human body back then. Bones, muscles, all of it.

2:36 Exactly. He was the ultimate expert on our physical bodies. But even though he studied bodies all day, he was deeply fascinated by the invisible part of us, the mind.

2:48 Why? Did he think the mind was completely different from the body?

2:53 He did. He believed our minds were something special, and to prove it to people, he came up with one of the most famous and spooky thought experiments in all of history. Ibn Sina asked his readers to imagine a man who was created in a single instant out of thin air, already fully grown.

3:12 Wait, so he wasn't born as a baby. He didn't have to learn how to walk or talk or go to school?

3:19 Exactly. He has no past whatsoever, zero memories of any life before this moment. And as soon as he is created, he is floating in empty air.

3:31 Like floating in outer space, with no gravity pulling him down.

3:36 Yes, floating perfectly in a total empty void. His eyes are covered with a thick veil, so he sees absolutely nothing but darkness. And there is no sound at all. Complete silence.

3:50 That sounds kind of terrifying, honestly. What about his hands and feet? Can he feel them?

3:55 No. His arms and legs are spread wide apart. They aren't touching each other, and they aren't touching anything else in the world.

4:03 So he can't even feel the brush of his own skin. What if he gets an itch? He wouldn't feel it.

4:09 He is completely unable to feel his own body. No heartbeat thump in his chest, no breath in his lungs, no sense of weight. Just total, heavy blankness.

4:21 Wow. I can't even imagine what that would be like. It's like being trapped inside a dark, quiet cloud.

4:29 So, here is Ibn Sina's big question for us to answer. In that exact moment, floating in the dark, feeling absolutely nothing, would this man still know that he exists? Hmm.

4:43 Let me really sit and think about that. He has no memories to tell him who he is.

4:48 Right. He doesn't know his name or where he came from or what a human even is.

4:53 And he can't feel his toes or his fingers or his stomach. He has no idea what he looks like, or if he even has a face. But is he still there? Does he know that he is something rather than nothing? I think he would. I mean, he'd be sitting there thinking, where am I? What's going on? Why is it so dark?

5:13 So he must know he exists.

5:15 Yes, Ibn Sina said the exact same thing. Even in total darkness, with no body to feel and no memories to rely on, the man would still have self-awareness. He would know, I am here.

5:28 Wait. But if he knows he exists, but he has zero proof that he has a physical body, then what exactly is he? What is doing the existing?

5:39 That is the absolute magic of the puzzle. Ibn Sina said, if you can be completely aware of yourself without being aware of your body, then the self must be something entirely different from the physical body.

5:52 So he's saying the mind, or the soul, is its own separate thing. It doesn't need the body to exist.

5:59 That's what he argued. He called it the soul. He thought this proved we are more than just a pile of bones and muscles. Our core self is invisible and separate.

6:09 But hold on a second. Doesn't modern science say we need our physical brains to think? Without a brain, the floating man couldn't think anything at all.

6:18 That is a really great pushback, Finn, and you are totally right to point that out. Today, neuroscience shows that our physical brains do the processing of all our thoughts and feelings.

6:29 Phew, okay. So the body is definitely important for thinking. We aren't just ghosts.

6:35 We definitely need our brains, but Ibn Sina's puzzle is still a huge deal, because it's about the experience of being conscious. What do you mean by the experience? Even if your physical brain is what makes the thoughts happen, the feeling of being you isn't just a physical object. It feels like an inner world.

6:55 The self feels like a mystery that science hasn't totally solved yet.

7:00 That makes sense. When I think a thought, it doesn't feel like a squishy pink brain inside my head doing math. It just feels like me.

7:10 Exactly. And that's why this thousand-year-old idea matters to us right now, today. Think about how much your physical body changes over your life.

7:21 Well, I used to be a tiny baby who couldn't even walk, and now I'm seven. I'm way taller, and I can run much faster.

7:29 Right. You grow, you get haircuts, you lose teeth. Scientists actually say that over time, almost every physical cell in our bodies gets replaced by new ones.

7:42 That's kind of weird to think about. Like, I'm made of completely different building blocks than I was when I was two years old.

7:49 You are. But do you feel like a different person inside?

7:54 No, I still feel like the exact same Finn. I'm just bigger and I know more stuff.

7:59 That is what Ibn Sina wanted us to see. The you that experiences life, the part that thinks and feels and wonders, is more than just a collection of bones and skin. Your true identity isn't just your physical parts.

8:16 That's actually really comforting. It means no matter how much I change on the outside, or even if I break a leg or get sick, I'm still totally me on the inside.

8:26 It is super comforting. And here is a crazy fun fact about this idea. Have you ever heard the famous quote, I think, therefore I am?

8:37 Yeah, I think I've heard that in movies or something. Who originally said it?

8:42 About 600 years after Ibn Sina wrote about the floating man, a famous French philosopher named René Descartes reached almost the exact same idea.

8:53 Wait, he came up with the same answer six whole centuries later.

8:57 He did. Descartes wondered if he could doubt that everything in the world was real. And he realised the only thing he couldn't doubt was that he was thinking. And if he was thinking, he must exist.

9:11 Wow, it sounds like he and Ibn Sina would have been really great friends if they lived at the same time.

9:17 Alright, Finn, quiz time!

9:19 Okay, I'm ready.

9:21 First question. What was the name of the Persian doctor who came up with this puzzle? Next one. What time period did he live in? Question three. In the thought experiment, what is the man doing? Here's number four. Did the floating man have any memories? Last question. What famous philosopher had a similar idea six hundred years later?

10:02 Great job! Let's see how you did. The first answer is, his name was Ibn Sina, also known in Europe as Avicenna. For question two, he lived in the early 1000s during the Islamic Golden Age. Number three, the answer is, he is floating in empty air, completely unable to feel his body. Question four, no, he was created in a single instant with zero memories.

10:31 And the final answer is, it was Descartes, who said, I think, therefore I am.

10:38 You know, I might never understand exactly how my mind and body work together, but it's really cool to think about.

10:45 I totally agree. It's okay to sit with those big mysteries. We don't need all the answers right now. The fun part is just wondering about them together.

10:55 If you liked Imagining the Floating Man with us, please leave us a five-star review. Just scroll down on your app and tap the stars. It really helps us out. And be sure to follow us here and check out our sister shows. History and Science is not boring, and maths is not boring. Go give those a listen and a follow as well.

11:16 Want your name on the show? Send us an email at hello at kidopoly.com. See you next time on Philosophy is not boring.

11:25 Bye everyone.