The Autonomic Nervous System

The Autonomic Nervous System has been found for example by Sigmund Freud in the middle of the 19th Century, and then we, Human Beings, have become familiar to it.
But at the same tme the idea of the Autonomic Nervous System is also rather very difficult to understand, and so it is very important for us to understand the theory of the Autonomic Nervous System exactly.
The Autonomic Nervous System is just the real situations of the Autonomic Nervous System, but at the same time the Autonomic Nervous System is not the object of our sense perception, and so it is very difficult for us to knowtice the real situation of the Autonomic Nervous System, but it is necessary for us to grasp the real situations of it inevitably.
The Autonomic Nervous System is absolutely different from the Brain-Spinal Nervous System. In the case of the Brain-Spinal Nervous System, all kind of the Brain-Spinal Nervous System are recognizable, but in the case of the Autonomic Nervous System, they are not recognizable. Is it necessary for us to have a kind of nervous system, which is not recognizable? Usually we feel that it might be absolutely useless for us to have a kind of the Nervous System, which is absolutely unrecognizable at all. But in the case of the Autonomic Nervous System it is perfectly unrecognizable. Why is it useful for the Autonomic Nervous System only can be useful, even though it is usually unrecognizable? I think that in the case of the Autonomic Nervous System the miscellaneous things and phenomena can be known relying upon the function of the Autonomic Nervous System itseif. Even the function of the Autonomic Nervous System is not so clear, relying upon the function of the Autonomic Nervous System, fortunately we can find so many valuable functions of the Autonomic Nervous System actually, and so we can expect that we, Human Being, will be able to find so miscellaneous and so gaugeous facts in the Universe in future relying upon the Autonomic Nervous System.