资料题：The main idea of this passage is that（　）。

Everyone talks about the”five" senses of man. And it' s true that we get our information about the outside world from our sense of sight, hearing, smell, touch and taste. Researchers tell us that the sense of sight -our visual sense- gives us up to 80% of what we know about the world outside our bodies; while the other senses, the auditory (hearing), the olfactory (smell),the tactile (touch), and the gustatory ( taste) bring into our brains information about the other twenty percent of what is happening. But there are two other senses that we cannot get along without, though they are very seldom given any credit for helping us to survive in this difficult world. These are the sense of balance, and the kinesthetic sense.The sense of balance, without which we would act like a drunkard after a heavy bout withthe bottle, is located in the inner ear. The inner ear contains three curved tubes ( the semicircular canals) filled with liquids. The shifting of these liquids activates nerve endings in the linings of the canals, and nerve impulses from these nerve endings help our brains to keep us upright.The kinesthetic sense is actually made up of nerve impulses that arise from nerves planted in close contact with our muscles. These nerve messages are constantly telling us what position our limbs, trunk and head are in. They serve as a continuous "feedback" system to help us knowhow to move our various parts, and when to hold them still. Otherwise, we would lack the coordination to run, jump, dance the twist, or even sit still. Incidentally, the word "kinesthetic" comes from two Greek words meaning "motion”and "feeling" . The kinesthetic sense gives us ourideas about our own motion.