How do you know you're real?
你如何意识到自己的真实存在？
It's an obvious question until you try to answer it, but let's take it seriously.
这是个显而易见的问题，但回答起来不容易，让我们严肃地讨论一下。
How do you really know you exist?
你如何才能真正意识到自己的存在？
In his "Meditations on First Philosophy," René Descartes tried to answer that very question,
勒内·笛卡尔在他的《第一哲学沉思集》中试图回答这个问题，
demolishing all his preconceived notions and opinions to begin again from the foundations.
他推翻了所有先入为主的概念，从根源上重新思考。
All his knowledge had come from his sensory perceptions of the world. Same as you, right?
他所有的知识都来源于他的感官，对这个世界的洞察。你也是这样，对吗？
You know you're watching this video with your eyes, hearing it with your ears.
你知道自己在用眼睛看这个视频，用你的耳朵听声音。
Your senses show you the world as it is.
你的感官告诉你这个世界是什么样子的。
They aren't deceiving you, but sometimes they do.
感觉器官并没有欺骗你，但有时候也会欺骗。
You might mistake a person far away for someone else, or you're sure you're about to catch a flyball, and it hits the ground in front of you.
从远处看，你或许会把一个人当作另外一个人，或者你确定可以抓住飞来的棒球，可是它却掉在地上。
But come on, right here and now, you know what's right in front of you is real.
但是不管怎样，此时此刻，你知道面前的一切都是真实的。
Your eyes, your hands, your body: that's you.
你的眼睛、你的手、你的身体，组成了你。
Only crazy people would deny that, and you know you're not crazy.
只有疯子才会不承认这个事实，你知道自己不是疯子。
Anyone who'd doubt that must be dreaming.
对这一点持怀疑态度的人一定是在做梦。
Oh no, what if you're dreaming? Dreams feel real.
噢对了，如果你真的是在做梦呢？梦给人真实的感觉。
You can believe you're swimming, flying or fighting off monsters with your bare hands, when your real body is lying in bed.
你觉得自己在游泳、在飞翔、在赤手空拳地和怪物搏斗，可你的身体依然躺在床上。
No, no, no. When you're awake, you know you're awake.
不不不，你在醒过来之后知道自己是清醒的。
Ah! But when you aren't, you don't know you aren't, so you can't prove you aren't dreaming.
可是，当你睡着的时候，你并不知道自己是睡着的，所以你并不能证明你现在不是在做梦。

Maybe the body you perceive yourself to have isn't really there.
或许你感知到的自己的身体，其实并不存在。
Maybe all of reality, even its abstract concepts, like time, shape, color and number are false, all just deceptions concocted by an evil genius!
或许所有的现实，甚至那些抽象的概念，包括时间、形状、颜色和数字，都不是真实的，所有的一切都是一个邪恶天才捏造出来的。
No, seriously. Descartes asks if you can disprove the idea that an evil genius demon has tricked you into believing reality is real.
严肃地说，不是这样的。笛卡尔在书中问到，你是否可以证明的确没有一个邪恶的天才欺骗你相信周围的世界是真实的。
Perhaps this diabolical deceiver has duped you.
或许这个邪恶的骗子真的欺骗了你。
The world, your perceptions of it, your very body.
让你相信周围的世界，相信自己的感知、自己的身体。
You can't disprove that they're all just made up, and how could you exist without them? You couldn't! So, you don't.
既然无法证明这一切都不是捏造出来的，那么你怎么能在没有这一切的环境中生存呢？你不能，所以你并不是在这样的环境中生存的。
Life is but a dream, and I bet you aren't row, row, rowing the boat merrily at all, are you?
生活就是一场梦，我相信你绝不是永远兴高采烈地划着这艘船，对吗？
No, you're rowing it wearily like the duped, nonexistent doof you are/aren't.
当然不是，你就像一个受骗的傻瓜，或者像一个你是或不是的一个根本不存在蠢货，疲惫不堪地划船。
Do you find that convincing? Are you persuaded?
这么说有道理吗？你被说服了吗？
If you aren't, good; if you are, even better, because by being persuaded, you would prove that you're a persuaded being.
如果还没有被说服，很好，如果已经被说服，那更好了，因为如果被说服了，说明你是一个有思想的存在。
You can't be nothing if you think you're something, even if you think that something is nothing
如果你认为自己是某种事物，那就不能说你什么都不是。即使你认为自己是“什么都不是”，
because no matter what you think, you're a thinking thing, or as Descartes put it, "I think, therefore I am," and so are you, really.
因为无论你怎样认为，你都是一个有思想的个体。或者就像笛卡尔所说：“我思故我在。”你也是这样，真的。