The Moving Thumb
Philosophers spend a lot of time pointing out that we don’t really see the world and that what we really see is what our brains make of the world. Too much of this kind of thing can make you want change your major to Business Administration.
Not ‘Windows To The World’
But science has shown that those philosophy types actually have a point. Here’s a simple demonstration you can do to show that your brain doesn’t just take in information, but always interprets that information.
Hold your arm out and stick your thumb up in the air. While looking at your thumb, slowly move your hand back and forth. Next, hold your hand still and slowly move your eyes back and forth.
Why did your thumb seem to be moving in the first instance and not in the second? The same image was sent to your retina, but in one instance you felt your hand was moving and in another you felt your hand was still. This shows that our brains aren’t just open windows through which the world pours. They are always interpreting the information they receive.
Always Interpreting
In this case, your brain knew your eyes were moving, and it interpreted the change in visual images as coming from inside your head. When it isn’t told your eyes are moving, your brain reads the same image as motion taking place outside your head.
This is the same reason lying down on the bed doesn’t make you immediately panic when you see the room turn on its side. In fact, your brain is always seeing the world move and deciding whether that motion is “in here” or “out there.”
移動(dòng)的拇指
哲學(xué)家花大把時(shí)間指明我們并未真正看到這個(gè)世界，我們真正看到的是我們的大腦制造的世界。太多這種事使你想轉(zhuǎn)專業(yè)學(xué)工商管理。
并非世界之窗
但科學(xué)已顯示這些哲學(xué)類型事實(shí)上有要點(diǎn)。你可以做個(gè)簡(jiǎn)單的證明來(lái)證實(shí)你的大腦不止攝入信息，但也總是解釋信息。
伸出你的胳膊，豎起拇指。當(dāng)你看拇指的時(shí)候，慢慢前后移動(dòng)手掌。接下來(lái)，保持手掌靜止，慢慢前后移動(dòng)你的眼睛。
為什么你的拇指在第一個(gè)例子里看起來(lái)移動(dòng)了而在第二個(gè)情況里沒(méi)有？同樣的圖像被投入視網(wǎng)膜，但一個(gè)例子里你覺(jué)得手移動(dòng)了，另一個(gè)例子你覺(jué)得手是靜止的。這解釋了我們的大腦不僅是世界洶涌時(shí)打開(kāi)窗戶，它們還總是詮釋獲得的信息。
總是詮釋
在此例中，你的大腦知道眼睛在移動(dòng)，它將視覺(jué)圖像的變化解釋為來(lái)自大腦內(nèi)部的變化。當(dāng)大腦沒(méi)有發(fā)覺(jué)眼睛在移動(dòng)時(shí)，大腦會(huì)將同樣的視覺(jué)圖像理解為是在大腦外部發(fā)生的變化。
這與躺在床上看房間傾斜不會(huì)立刻感到恐慌是一個(gè)道理。事實(shí)上，你的大腦總是看世界轉(zhuǎn)動(dòng)并且在思考這運(yùn)動(dòng)是在內(nèi)部還是在外部。
