The long-standing contradiction and conflict between empiricism and rationalism in the history of philosophy is due to the contradiction between the subject's own sensibility and rationality.

The main differences between rationalism and empiricism

First, the source of knowledge.

The issue of "the source of knowledge" debated by rationalism and empiricism in modern philosophy is mainly whether there is a "natural idea". Generally speaking, empiricists all advocate that knowledge originates from sensory experience and deny "natural idea". On the contrary, rationalists deny that correct knowledge originates from sensory experience and affirm "natural idea" in different ways.

empiricists believe that "all our knowledge is obtained from feelings" (Hobbes: On Objects, see Philosophy of Western European Countries in the 16th-18th Century, Commercial Press, 1975, p. 9) "All our knowledge is based on experience; In the final analysis, knowledge is derived from experience. " (Locke: Theory of Human Understanding, see Philosophy of Western European Countries in the Sixteenth-Eighteenth Century, Commercial Press, 1975, p. 366) In the view of empiricists, all ideas are induced, summarized and abstracted from the perceptual content of sensory experience by thinking; All concepts can be reduced to different combinations of feeling and feeling, and everything in reason exists in the perceptual content of sensory experience; Anything that can't be found in perceptual content is either wrong or beyond human reason; The understanding function of thinking can only be based on the concept of feeling to express the object. (See Zou Huazheng: A Study on the Theory of Human Understanding, People's Publishing House, 1987, p. 6)

Contrary to empiricism, rationalists affirm the "natural concept" in different forms. Descartes pointed out that there are three sources of ideas: one is "natural" general abstract ideas and principles in mathematics, logic, religion and ethics, the other is from the outside, such as hearing, seeing and feeling, and the third is "imaginary" ideas that do not exist at all, such as flying horses and mermaids. For these three cases, Descartes believes that the ideas derived from the outside, like the imaginary ones, have no truth, and only the general ideas derived from my own nature have truth. That is to say, the understanding of "truth" can only be "natural". Leibniz further suggested that sensory experience can only perceive individual accidental phenomena, but cannot reveal the "universal inevitability" of truth. He also sharply described empiricists as "purely relying on experience and only relying on examples to guide themselves" like livestock, so they could not adapt to the complex and changeable existence. "The reason why people are so easy to catch animals and pure empiricists are so easy to make mistakes is this reason". (Leibniz: A New Theory of Human Reason, see Philosophy of Western European Countries in the Sixteenth-Eighteenth Century, p. 53) In the view of rationalists, thinking itself has the principle of innate knowledge beyond sensory experience, and the object can only be recognized by people under the grasp of the principle of innate knowledge; Cognition can't be reduced to different combination forms of feeling and feeling, but it has more natural ideas as cognitive principles; The understanding function of thinking is to understand the object according to its own inherent natural principles. (See Zou Huazheng: A Study on the Theory of Human Understanding, p.6)

From the above analysis, we can see that empiricism and rationalism have their own problems that are difficult to solve. "For empiricism, is cognition simply the deformation of feeling, and does it only originate from sensibility, but not from rationality at the same time?" "For rationalism, is the dynamic understanding of thinking a natural idea, and does knowledge only originate from rationality, but not from sensibility at the same time?" (ibid., page 61)

The problem that deserves special attention here is that people always look at the source of knowledge from the perspective of "experience", so they often simply assert that empiricism is right and rationalism is wrong, without reflecting on the complex relationship between sensibility and rationality. In this regard, Engels pointed out that "our subjective thinking and the objective world are subject to the same law, so they cannot contradict each other in their own results, but must be consistent with each other. This fact absolutely dominates our entire theoretical thinking. It is the unconscious and unconditional premise of our theoretical thinking. " As for this "premise", the 18th century materialism, as empiricism, "is limited to proving that all the contents of thinking and knowledge should originate from perceptual experience, and it also puts forward the following proposition: anything that has never been experienced in the sense does not exist in reason. Only modern idealistic and dialectical philosophy, especially Hegel, has studied this premise from the form. " (Selected Works of Marx and Engels, Volume 3, page 564)

Therefore, in understanding the source of knowledge, we should not only admit that "all thinking and knowledge should originate from perceptual experience", but also explore the inherent dynamic role of thinking from the aspect of "form". What needs to be pointed out in particular is that people's understanding should not only form the "representation" about the experience object, but more importantly, form the thought of "universal inevitability" about the object. The thought of "universal inevitability" is not directly and readily induced, generalized and abstracted from the perceptual content of sensory experience, but it is necessary to affirm that thinking grasps the law of existence, that is, the dynamic role of thinking, from the source of knowledge. Therefore, on the issue of the source of knowledge, we should not only go beyond the accustomed "experience" position, but also get rid of the rationalist "innate concept theory", which requires us to understand the source of knowledge materialistically and dialectically.

second, about the method or logic of cognition.

The opposition between empiricism and rationalism on the source of cognition already contains different understandings about the method or logic of cognition. This different understanding is the opposition between the individual and the general problem: can the understanding of universal inevitability be formed from individual perceptual experience?

Francis, the founder of modern empiricism? Based on the principle that knowledge originates from experience, Bacon formed his "induction" from individual perceptual experience to universal inevitability. This is bacon's "new tool".

Bacon criticized Aristotle's syllogism deductive logic and formed his "new tool" inductive logic. Bacon pointed out that "just as existing science can't help us find new things, existing logic can't help us find new science". (Bacon: New Tools, Commercial Press, 1984, p. 1) This is because, "syllogism cannot be used in the first principle of science, and it is invalid to use it in the middle axiom. Because it is not as subtle as nature. Therefore, it can only be strong to agree with the proposition, but not to grasp things. " (ditto) In Bacon's view, only inductive methods can make knowledge rise from empirical facts to general principles.

The basic contents of Bacon's induction method are: on the basis of observation and experiment, the corresponding perceptual experience materials are obtained; Sorting and classifying perceptual materials into positive examples, negative examples and examples whose properties have changed under different conditions, and making a comparative study of these three types of examples; Reject non-essential things, discard useless materials and leave useful materials; Summarize the remaining materials and get the general principle. (See Wang Tiancheng: The Theory of Creative Thinking, Jilin Education Press, 1989, p. 7) Bacon believes that this induction can enable people to expose different levels of natural laws step by step and prevent people from making unnecessary guesses beyond experience. Contrary to empiricism, Descartes, the founder of modern rationalism, believes that in the pursuit of truth, we must first explore an unquestionable principle and form a universal thought on the basis of this principle. This is Descartes' new deductive logic. The basic rules of this new deductive logic or deductive method are as follows: First, never accept anything that I don't clearly know as true, that is to say, be careful to avoid hasty judgment and prejudice, and only put those things that are clearly presented to my mind so that I can't doubt them at all into my judgment; Article 2: divide every problem I have investigated into small parts as much as possible until it can be solved satisfactorily; Article 3: Guide my thoughts in order to start with the simplest and easiest objects to understand, and gradually rise to the understanding of complex objects. Even those objects that have no natural order with each other, I will set an order for them. The last one: list all the situations as completely as possible and examine them as generally as possible, so that I am sure that there is nothing missing.

It is noted that Descartes' new deductive logic is no longer the traditional deductive logic and its development in modern western mathematical logic. Traditional deductive logic is a kind of extension logic, that is, it relies on the extension relationship between concepts of universality, particularity and individuality to form major premise, minor premise and conclusion. Descartes' deductive logic is the connotative logic in which thoughts rise from simplicity to complexity and from abstraction to concreteness. This connotative logic about the development of thought itself, to Hegel, the master of German classical philosophy, constitutes the logic about the movement of human thought with dialectical development of concepts. The direct significance of Hegel's concept dialectics lies in its logic about the movement of human thought and the development of human thought.

when we understand the connotation logic of Bacon's empirical induction and Descartes' rationalism, we must also see that, as the two beginnings of modern philosophy, there are some similarities that cannot be ignored: First, the induction created by Bacon and the connotation logic developed by Descartes are the products of trying to surpass the traditional deductive logic on the basis of modern science. They do not completely deny syllogism and its logical rules, but oppose the absolutization and authority of traditional deductive logic; Secondly, they all set out from breaking rigid concepts and prejudices and tried to realize the creativity of thinking with new methods or logic. Bacon's exposition of racial illusion, cave illusion, market illusion and theater illusion, and Descartes' exposition of eliminating false ideas are all aimed at preventing the "prejudice" dominated by ancestors from misleading and binding people's understanding

thirdly, about the reliability of cognition, that is, which is more reliable, sensory experience or rational knowledge.

empiricists believe that "error or falsehood is not in the senses, and the senses are not active, but only accept images ... error or falsehood is in judgment or in the mind; The judgment or mind does not give due careful treatment, and fails to notice that things that are far away are small and vague just because they are far away or for other reasons. The same is true in other cases. " (See Gassendi: Questioning Descartes' Meditation, The Commercial Press, 1963, p. 75) This blames "error" or "falsehood" on "judgment" or "mind", that is, on human reason.

On the contrary, rationalists think that feelings are "deceptive". Descartes said: "Because I have observed many times: the towers look round from a distance, but they look square at close range, and the colossus standing on the top of these towers look like figurines at the bottom;" In this way, on countless other occasions, I have found that the judgment of the external senses is wrong. " (See Philosophy of Western European Countries in the Sixteenth-Eighteenth Century, Commercial Press, 1975, p. 179) When analyzing the philosophical thoughts of Dutch philosopher Spinoza, Chinese scholars put forward: "The rationalist Spinoza inherits Descartes' epistemological thoughts and divides knowledge into three categories: the first category is perceptual experience knowledge, including hearsay knowledge and general experience; The second category is reasoning knowledge; The third category is rational intuition. He said:' only the first kind of knowledge is the cause of error, and the second and third kinds of knowledge are necessarily true.' It can be seen that Spinoza also rejects perceptual experience and only trusts the reliability of rational knowledge. (See Series 5 of Studies on the History of Foreign Philosophy, Shanghai People's Publishing House, 1982, p. 14)

In the development of modern philosophy, empiricism and rationalism gradually moved from two extremes to affirm the respective rationality of sensory experience and rational knowledge, but they have always separated sensibility from rationality. Kant, the founder of German classical philosophy, put forward the principle of combining perceptual intuition with rational thinking on the basis of summing up empiricism and rationalism of modern philosophy. His famous saying is: thinking without sensibility is empty, intuition without concept is blind. Hegel, the master of German classical philosophy, believes that although Kant emphasizes the "combination" of perceptual intuition and intellectual thinking, in Kant's view, "thinking and intellectuality still remain a special thing, and sensibility is still a special thing, and the two are only combined in an external and superficial way, just like a piece of wood wrapped around a leg with a rope". (Hegel: Lecture Notes on the History of Philosophy, Volume 4, Commercial Press, 1983, p. 271) Hegel put forward the dialectical unity of sensibility and thinking for the first time in the history of philosophy. He asked for a "leap" from sensibility to rationality by virtue of the initiative of rational thinking. However, to truly understand the relationship between sensibility and rationality dialectically, and truly transcend the one-sidedness of empiricism and rationalism, we need to look at the understanding of treating others from the perspective of human practical activities and their historical development. This practical epistemology is a revolutionary change of Marx's epistemology.

2. Popper's philosophical system focuses on critical rationalism, which is quite different from classical empiricism and its observation-induction method. In particular, Popper opposed the observation-induction method. He believed that scientific theories were not applicable to the universal and could only be evaluated indirectly. He also believes that scientific theories and all the knowledge that human beings have mastered are just speculations and assumptions, and people inevitably mix imagination and creativity in the process of solving problems, so that problems can be answered within a certain historical and cultural framework. People can only rely on the only data to establish this scientific theory. However, in addition, it is impossible to have enough experimental data to prove that a scientific theory is absolutely correct. (For example, people came to the theory that "sheep are white" after testing 1 million sheep. However, as long as there is a black sheep outside the test, the previous theory can be proved wrong. Who can test sheep endlessly to prove the absolute correctness of the theory that sheep are white? The "asymmetry between authenticity and falsehood" deduced from this "fallibility" principle (it can't be proved, only falsehood can be proved) is the core of Popper's philosophical thought.

3. Einstein opposes quantum mechanics because it attracts potential in the research object of physics (which is different from the epistemological category of physicists). He said, "God doesn't roll dice" to show his opposition. The main point of this statement is that the dice game is based on the law of opportunity, and Einstein believes that the latter concept can only find its scientific significance in the limited epistemological limitations of the cognitive subject, which exists in the relationship between the cognitive subject and the all-encompassing scientific knowledge object. Therefore, when it comes to that object in ontology,