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6.24 Perception is the faculty that allows us to process information in the present as we take it via our senses. Again, studies have shown that people will fill in information that they thought they perceived even when they didn`t.
In cognitive psychology, we have a phrase for this kind of inaccurate filling in of details--- its called: A Blind Spot. So that particular area of the eye is incapable 不能of detecting images. It produces “A Blind Spot” in our field vision.
We are unaware of it, because the brain fills in what it thinks belongs in its image, so the picture always appears complete to us. But the term “blind spot” has also taken on a more general meaning--- it refers to people being unaware of a bias that may affect their judgment about the subject. And the same “blind-spot phenomenon” that affects memory and perception also affects imagination.
6.25 Now, one way to 方式um, modify the overcome this mismatch in the density of air and water would be…if you travels through velocity of the sound wave, make it precisely match the speed at which water. And that's exactly what marine biologists have discovered发现 the melon Note that the bursa, these little projections at the rear of the melon, are right up against the air-filled nasal sacs. And these bursa, it turns out, are what's responsible for transferring sound to the melon. The sound waves are then transmitted by the bursa through the melon. First through a low velocity core, and then through a high velocity shell, where their speed is increased before they are transmitted into the surrounding seawater. So now the signals can be efficiently transferred into the water, with minimal reflection.
6.26 Turns out结果发现 that the lower jaw, well, it is made of a specially thin bone. And it is very sensitive to vibrations, to sound energy traveling through the seawater. It turns out that the jaw is primarily responsible for capturing and transferring returning sound waves to the dolphins inner ear. So these rapid clicks that are sent out bounce off objects, maybe a group of fish swimming over here, a boat coming from over there. The sounds bounce off them and the lower jaw captures the returning sounds, making it possible for the dolphin to sense what's in the surrounding water and decide where to swim.
3需要推理的术语的意义
6.27 Let’s start with one philosophical view---- foundationalism
Foundationalism is the view that our knowledge claims, what we think we know, that is they need to have a base. And think of knowledge as a house, you need a solid foundation on which to build your house. And if you have a strong foundation, your house is more likely to be solid. Well, foundationalists think the same thing is true of knowledge. If you have a solid base for your knowledge claims, then your knowledge structure is more likely to be strong, valid, true.
First, you need some good foundational knowledge claims, and then the rest of the knowledge claims can be based on these.
6.28 Take John Locke for instance.
Locke’s viewpoint essentially was that when humans are born, their minds are like blank slates. That is we don’t have any kind of knowledge when we are born. We get our knowledge from our senses, you know taste, touch, smell, sight, hearing. So, when we look at the world, first as babies and then as we grow, that’s where knowledge comes from. Our senses, our experiences serve as the foundation for our knowledge.
NOw, for a very different view, let’s turn to another philosopher---- Rene Descartes.
Descartes thought that you have to go much deeper to find the foundations. He believed that our senses are not to be trusted. So he wanted to find a more solid foundation for knowledge. He began with what has come to be called methodological doubt. And when we say methodological doubt. Well... Descartes believed that everything should be questioned, that is, approach it with doubt and that if you could find one thing that cannot be false, that one thing would serve as 作为a foundation for all other knowledge claims.
So unlike John Locke, Descartes doubts that knowledge comes to him from his senses.
6.29 Chimpanzees and other primates, chimps, gorillas, orangutans, and of course, humans. But it’s also been found in elephants and bottlenose dolphins, abit of surprise. It’s very rare. Most animals don’t have it. And it’s called mirror self-recognition, or MSR
Student
Well, how does it work? I mean, how do researchers know if elephants or chimps recognize themselves?
Professor
Reserachers give them a mirror mask test. In the mirror mark test, researchers put a mark on the animal where the animal is unable to see it or smell it or feel it, likeon the sides of their head, without looking in the mirror
NOw, typically, when animals first see themselves in the mirror, they think they are seeing another animal. Often they will look for this animal behind the mirror. They may even exhibit aggressive behavior.
But some animals, after this period of exploration, exhibit behaviors that show they know they are looking at themselves. For instance, elephants will touch the marker on their heads with their trunks.
6.30 Well, we definitely have to anchor it at both ends. So what we need is a really tall tower here on the ground right at the equator and a satellite in geostationary orbit around the Earth. There is a reason I mentioned that figure of 36,000 kilometers. That’s about how high an object would have to be orbiting straight up from the equator to constantly remain directly above the exact same spot on the rotating planet Earth. So once you are in this geostationary orbit right over the tower, just lower your carbon nanotube cable down from the satellite, tether it to the tower here on Earth. And there you have it!
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