"I think therefore I am" is what the French philosopher Descartes said: I think therefore I am in the highest metaphysics. Times have changed, and your shadow is everywhere. Through the dust of the century, because of an idea, your light shines all the way in the garden of human spirit. You are an evergreen leaf. What does "I think therefore I am" mean? "This is an important proposition of Descartes, which is a truth in his view. Descartes first doubted the truth of everything, such as eating, dressing and so on, which are common to ordinary people. For him, the performance of human activities in thinking can be divided into reality and dreams. However, the authenticity of the two is different. The former is real and the latter is illusory. But for a person, it is impossible for thinking to know clearly whether what he feels is in reality or in a dream. When no one is dreaming, he will think that what he perceives is untrue, and he will not think that he is dreaming. Only when. So Descartes doubts the truth of everything, and this assumption can be established in Descartes' view. So truth and unreality have no absolute meaning, because no one can say for sure that he is not dreaming. However, there is no doubt about one proposition, which I just said, and that is "I think, therefore I am", because no matter in reality or in dreams, one can't deny that one is perceiving and thinking, so as long as one is perceiving and thinking, he must be real, because only the living have this ability. Descartes may be the greatest philosopher in French history. Heidegger, a great German existentialist, once said: "Since Leibniz, the great development (change) of Descartes' basic theory has not surpassed this basic theory at all, but only expanded its metaphysical breadth, thus creating a premise for19th century." However, in the eyes of people who believe in empiricism and materialism, Descartes has a fatal handle, that is, his famous saying that has echoed for centuries: "I think, therefore I am." This famous saying, regarded by Descartes as the starting point of his own philosophical system, was regarded as the general representative of extreme subjective idealism in eastern European academic circles in China in the past and now, and was severely criticized. Many people even regard Descartes as "putting the cart before the horse" and "ridiculous" on the grounds that "existence must precede consciousness" and "there can be no thought without body". In our reading forum, a netizen specially wrote the pseudonym "I am thinking" for himself to show his firm belief in materialism. It is an extremely difficult course to absolutely doubt Descartes' philosophical course. The starting point of his philosophical pursuit is the most fundamental and thorough doubt about human cognitive ability. Descartes once described the beginning of his thinking process like this: "I think that everything closest to' truth' comes from feeling and the transmission of feeling. However, I find that these things often deceive us. Therefore, the only wise thing to do is never completely believe those things that have deceived us even once. " The help of the outside world to our cognition is so unreliable. So, what are our active perceptual activities (called "practice" by dialectical materialism) and thinking? These activities often appear in dreams, making it impossible for us to distinguish between "dreams" and "waking up". Therefore, I have to wonder whether the whole world is just a dream (we remember the story of Zhuangzi and Butterfly). Starting from these simple and preliminary "doubts", Descartes pushed his doubts to the extreme: "I would like to assume that the source of all truth is not a kind God, but an equally cunning and magical devil, who tried his best to lead me astray. I am willing to assume that the sky, air, land, shape, color, sound and all external things are just the presentation of that deceptive dream, and the devil will exchange them for my credulity. I want to observe myself like this: it seems that I have neither hands nor eyes, nor body, nor blood, nor all organs, but I just believe in these. " ("Discours de la Methode") It can be seen that Descartes' doubts are not doubts about certain specific things and specific principles, but absolute doubts about human beings, the world and God. From this absolute doubt, Descartes should lead to unquestionable philosophical principles. Descartes went on to say, "Just when I tried to believe that all this was false, I found that something (which was doubtful for me) was essential, and that was the thinking me! Because the fact that' I think therefore I am' transcends the doubts of all skeptics, I will regard it as the first principle of the philosophy I pursue. " "Discours de la Methode", through Descartes' exquisite description of his own philosophical course, we can clearly know that the meaning of this famous saying is not: Because I think, I exist. But: I realized (my) existence through thinking, and I knew "existence" from "thinking". The Chinese expression of "I think, therefore I am" is very vague and inaccurate, which is basically the cause of our compatriots' misunderstanding of Descartes. However, in this case, we in China are not the only lost sheep in philosophy. For hundreds of years, European philosophers have treated him in the same way. The root of this misunderstanding is the Latin translation of Descartes' French masterpiece Discours de la Methode. In the Latin translation of this book, you can see: cogito ergo sum! ("I think, therefore I am!" If the meaning of "I" is removed from the translation of this sentence, it is probably more in line with the original intention to translate it directly into cogitans sum. Because most of the philosophical works at that time used Latin, and French was only a local language, this Latin spread like wildfire and became synonymous with Descartes' philosophy, while the original French texts Jepense and DoncJesuis could not be overwhelmed. Descartes' original intention was to establish an unquestionable academic method system, but the starting point of his philosophical principles was widely misunderstood from the beginning, and history was so unfair.