Why is Descartes so important? He is an epoch-making philosopher and a link between the past and the future.
This question is very important because it contains a hypothesis. If he is a philosopher, then he is new, because modernity emphasizes the influence of modern science on human time and needs a new philosophy to face him.
If he is a philosopher who links the past with the future, that is, Descartes is a transitional role between medieval philosophy and modern philosophy, this is a very important point of view.
Descartes pursues 100% certain knowledge, which is his goal, which is achievable. Did Descartes achieve 100% certainty of knowledge? If it is done, then we can say that modern science has also done it, because Descartes wants to answer that 100% of the determined knowledge has been done by science. This is the main reason why he pursues 100% truth.
In fact, everyone will understand that it is impossible for us to achieve 100% confident knowledge. We are also glad that people can't have 100% definite knowledge, which means that the pursuit of knowledge can be sustainable. How to achieve and solve all the problems of knowledge in the process of pursuing knowledge? This is unlikely and will not be a good thing.
Descartes is a practical scientist and a devout Catholic, so the question before us is whether to create the world or to link the past with the future. Basically, we find that Descartes' philosophy contains the shadow of medieval philosophy, but it also inspires modern philosophy. Descartes, the shadow of medieval philosophy, also believed that man had a soul. In his view, human beings are in cognition, and mind and body are binary, which is a main place where Descartes can connect the past and the future.
In addition, Descartes is also a very important scientist. Descartes himself proposed an astronomical system, vortex cosmology. In fact, he also invented analytic geometry, combining geometry with algebra. Descartes was not only a mathematician but also an astronomer and an important philosopher. So from this perspective, we can know that Descartes is a person who actually participates in science. This question is very important, because the ideas and practices put forward by anyone who has never participated in science are very different from those who have not participated in science. If a layman looks at science, many people will think that science is great, certain and impressive, which is beyond our imagination and super successful. But in fact, people who participate in science first face many mysteries in the process of scientific invention and discovery, and in the actual work of science, there are also many imaginations and assumptions, and most importantly, there are many basic beliefs. So from this point of view, Descartes' philosophy wants to understand it completely, and it is necessary to know what philosophical work he is doing.
The most important content of Descartes philosophy is the method of doubt. When he emphasized the method of doubt, he had an idea. He said to give up unfounded cognition, and the content involved was very thorough. My experience comes from my five senses, smell, taste, touch, hearing and vision. This is the result of our experience, but they are limited, so my experience will not exist for the time being. You can't see from a distance, you can't hear from a distance, let alone smell. So my experience may be doubted, and then the environment we are in now.
The most special thing about Descartes' skepticism is that he is a mathematician himself, but he even doubts mathematics. In his Meditations, he said, "Is there a devil who can make our minds pretend that mathematics is possible, but it is actually wrong?"
Descartes is the link between the past and the future. He inherited the philosophy of the Middle Ages and initiated modern philosophy. He transformed theology into science through his philosophy, so it is understandable that medieval demons appeared in his explanation, otherwise he could not understand why Descartes was so important.
Descartes himself was a mathematician. What is the purpose of his way of asking questions? After we have eliminated all the suspicious parts, of course, we can't doubt the rest.
What must be true and cannot be doubted? As a mathematician, Descartes discovered a very important truth.
Mathematics is basically a system, with axioms first and then theorems through reasoning.
Descartes knew long ago that axioms can go wrong, and if axioms go wrong, theorems will go wrong. For example, in Euclidean geometry, the shortest distance between two points is a straight line, which is an axiom. This axiom can't go wrong in our sensory perception and empirical rationality, but in Einstein's theory of relativity, the nearest distance between two points is not a straight line.
However, there is one thing in mathematics that cannot be wrong. demonstration
There is no mistake in reasoning. How to make an axiom? When we get a theorem through reasoning, the result of axiom and theorem may be wrong, but the theorem will not be wrong. In this way, he put forward his most famous phrase "I think, therefore I am", combining a bad method with whether reasoning will go wrong. It is true that I am thinking, but I think the reason why I am thinking is the key. When we think that if we get this reasoning, we will get this part, and then we will say that as long as I think, then I exist.
I'm not thinking alone, so are you. After all people have similar thinking, there will be such a situation in the future, that is, all people exist, together, all people exist. I can only guarantee my existence. Who can guarantee the existence of everyone? Descartes was a mathematician, philosopher and scientist. He emphasizes the most fundamental logic, his doubts are also fundamental, and his cognition of reasoning is also fundamental. Then he assembled "I think, therefore I am", which basically combined all suspicious methods with all determinable knowledge, emphasizing that I think, therefore I am. This truth is clear, you will think so, and I will think so.
For Descartes, everyone has the ability to think.
Who can guarantee that everyone exists? Descartes said in Meditation that God can guarantee the existence of all people.
Descartes doubted the existence of sensory perception and our * * *, and now the situation turned into a memory, and then even mathematics was basically doubted, and even a demon was suspected to have completely deceived us. Illusion mathematics is calculated according to this, but mathematics is not calculated according to this. What is Descartes going to do?
Descartes is the result of the extension of the Middle Ages. For him, if there is evil, there is God. I want to rebuild my knowledge for him. He wants to emphasize that the certainty of this knowledge is 100%. Can you do that? Rebuilding knowledge is enough. Descartes' foundation of reconstructing knowledge is that I can't deny that my foundation is that something is thinking, and what I am thinking is not necessarily people. I don't know that I am alone, but I am thinking about this thing, so I exist. This is no problem.
But suppose all people, the external world we live in, all the conditions we live in, such as people having free will and people dying, all know this knowledge, and who can guarantee that this knowledge is correct in these contents? Descartes said that God can guarantee.
It is difficult for you to pursue 100% certain knowledge. Even if you have it, you are not sure that it is 100% knowledge. In fact, all knowledge may be challenged, criticized and restricted. This is a very important concept. However, having 100% knowledge is Descartes' goal, but he knows very well that the source of our pursuit of knowledge comes from faith, and we must believe that something should be like this. This belief, in fact, as long as it can be clearly stated, as long as it exists, there is no need to worry about whether it is 100% certain. No one can have 100% definite knowledge.
So it is unrealistic for us to pursue 100% certain knowledge.
We must have confidence in the pursuit of knowledge. This thing, starting from philosophy, even Plato is no exception.
Plato believes that knowledge is a belief that has been proved to be true, and it is a belief that has been proved to be true through our experience.
Our experience is limited and will not be permanent, but it is enough to prove true in the current state, but the real meaning is to have a belief.
So from this perspective, Descartes' greatest role in modern philosophy is neither science nor mathematics. His greatest place is epistemology. Because of Descartes' efforts, we later developed epistemology.
Descartes believes that the origin of knowledge is faith. Without faith, everything is impossible. If you blindly pursue the method of doubt, you won't have to learn anything at last.
In fact, the method of doubt has developed to the extreme. The Scottish philosopher Hume believes that if we pursue the extremes of doubt, in the end, we must deny cause and effect, even induction, even cause and effect. So in fact, Hume thinks that if you want to doubt, then you don't have to learn anything. Nothing is impossible, not only in science, but also in basic cognition. There is no way to be sure that you have cause and effect in the development of knowledge. If you can only deny cause and effect, then you will find that the whole knowledge is impossible.
Descartes put forward a very good understanding of this point from the beginning. If knowledge is of origin, it must have faith. With faith, you have a solid foundation. On this basis, you can revise and criticize him. You can criticize this new year step by step through rational development. In fact, the growth of human knowledge comes entirely from this constant criticism and constant revision. This is what we call the growth of knowledge. The reason why knowledge can grow is because it has been revised by experience from the beginning and developed step by step. Finally, this belief has been confirmed by experience and can be explained rationally. But it faces new bottlenecks and needs new breakthroughs, and new bottlenecks and new breakthroughs need new beliefs, so that we can make more rigorous assumptions and then accept the next empirical test.
So Descartes put forward not only epistemology, but also scientific epistemology. The development of the whole science is how to use our experience to test our beliefs, so as to gain knowledge that breaks through experience. And the result of this experience development process is scientific knowledge.