EMPIRICISM

Empiricism, more a philosophical presupposition than a definitive system, insists in general that knowledge begins with the senses and with sense experience. Some empiricists limit all knowledge to sense knowledge and deny the reality of universal ideas, necessary truth, and innate or a priori ideas (see sensism). This form of empiricism is opposed to rationalism and idealism, which attempt to deduce the nature of reality from the intelligible content of ideas in the mind. A less radical form of empiricism insists that experience be the final test for the validity of any idea or proposition, or holds that any knowledge transcending the data of experience can be only probable. experience itself has different meanings for empiricists. It may refer exclusively to sense data or to man's existential contact with external objects. For Locke, Hume, and Berkeley, it meant the impressions and ideas generated either by external objects or by the mind itself.

This article describes the various forms that empiricism takes in philosophical and scientific thought, surveys the historical development of empiricist attitudes, and concludes with a critical evaluation from the viewpoint of moderate realism.

Types of Empiricism. The principal positions that can be classified as empiricist include strict and relative empiricism, metaphysical empiricism, scientific empiricism, and logical empiricism. These may be characterized in summary fashion as follows:

Strict and Relative Empiricism. A strict or thoroughgoing empiricism refuses to recognize the validity of any knowledge that is not grounded in and verified by sense experience. Denying the validity of metaphysics, it substitutes association and habit for causality, and collections of secondary qualities for substance, tending in general toward skepticism and agnosticism. As opposed to this, relative empiricism holds that while sense experience gives rise to ideas, such experience can be intelligently grasped by the intellect to furnish a metaphysical insight into the nature of reality as such.

Metaphysical Empiricism. Relative empiricism can also be termed metaphysical empiricism, although the latter expression has a somewhat different meaning in contemporary philosophy, where it designates a limited metaphysics of finite being growing out of sensible experience. Such a metaphysical empiricism grants the quasi reality of universal ideas or categories, together with the reality of cause and effect, possibility and existence, and substance and accident. At the same time it restricts such categories to the area of finite being and is content with a limited and relative truth about this area. It is strictly opposed to any sort of transcendent metaphysics or to claims for absolute and unchanging truth.

This empiricism purposes to be objective and realistic, and attempts to escape from the skepticism generated by the strict empiricism of Hume and from the subjectivism of kant. At the same time it refuses to trust the ability of the human mind to rise above the finite and the temporal.

Scientific Empiricism. Scientific empiricists seek to unify the laws of science so as to deduce the laws governing particular sciences from unified principles. Behind this enterprise lies the conviction that only natural science can provide certain knowledge. Scientific empiricism is closely allied to logical positivism, linguistic analysis, and contemporary British and American analytical philosophy.

Logical Empiricism. This is the logical counterpart of scientific empiricism. The movement began in the 1920s at the University of Vienna with a group known as the Vienna Circle, composed of men such as M. Schlick, R. Carnap, L. Wittgenstein, P. Frank, and H. Reichenbach. Their aim was to construct a theory of meaning and knowledge that would reconcile the valid elements of rationalism and empiricism through the use of logic and the procedures of natural science. Mathematical or symbolic logic and linguistic analysis were their chief tools. Most logical empiricists adopt Hume's notions of causality and induction, insist on the tautological nature of mathematical and logical truth, and conceive of philosophy as a clarification of everyday language. They usually reject metaphysics as a pseudo-science based on pseudo-problems, having their source in linguistic confusion. One of their principal commitments is to the verifiability principle, which states that only those propositions can be held as true that are capable of actual or possible experiential verification.

Historical Origins. epicurus of Athens (341–270 b.c.), from whom epicureanism takes its name, was probably the first radical empiricist. For him, the criteria of truth are sensations, preconceptions, and feelings; and all knowledge is based on sensation. The universe is a void in which atoms move and combine with one another to form material things. These things continually emit minute particles that impinge on the corporeal soul of man and, forming images of themselves there, produce knowledge. His is a crude materialism, basically reducible to sensism. Zeno of Citium (c. 336–264 b.c.), the founder of stoicism, conceived of the universe as matter penetrated with and guided by an eternal fire. This fire he identifies with nature, the touchstone and key to all knowledge and wisdom.

Medieval Empiricism. The conflict between Platonic and Aristotelian thought was repeated in medieval thought in the persons of St. Augustine (a.d. 354–430) and St. thomas aquinas (1225–74), respectively. For St. Thomas, as for Aristotle, everything in the intellect is somehow grounded in sense experience; thus, Aquinas finds in the sensible world principles that explain the structure and intelligibility of all being. More empiricist in mentality was william of ockham (1290?–1349), who restricted human certitude to propositions having direct experiential reference. Since only singulars exist, and since all the singulars with which man makes contact are sensible, it is to the sensible world and to the concepts that stand for it that he goes for certitude. All other knowledge, for him, is abstractive and can give no real idea of existence. For example, Ockham sees no way in which either the existence of God or the existence and spirituality of the human soul can be rationally demonstrated. He does admit, however, that one can make an act of faith in the existence of realities transcending sensible experience.

Renaissance Period. The empirical tradition was carried on during the Renaissance chiefly by four thinkers. leonardo da vinci (1452–1519) conceived of nature as a product of the divine mind. For him, only by an investigation of nature can man return to its source and learn something of divinity. "Wisdom is the daughter of experience" was a favorite saying of his, and it is mathematics that enables one to interpret experience and come to an understanding of the rational order operative in nature. Juan Luis vives (1492–1540) is often credited with being the father of experimental psychology, since his approach to the human soul was based on introspection and experience. Tomasso campanella (1568–1639) was especially interested in harmonizing the new science with both a philosophy based on experience and the teachings of Christianity. He wrote a defense of Galileo in which he stated that if Galileo was to be proved wrong, it must be done by new observations and not by a priori judgments. Galileo galilei himself (1564–1639) can be considered an empiricist insofar as he held sense experience to be necessary for ascertaining the existence of objects before mathematical method could be applied to them. Yet experimental verification of mathematical conclusions, while helpful in some cases, was not regarded by him as necessary for those who understood his mathematical method.

British Empiricists. Francis bacon (1561–1626), dissatisfied with rationalism and scholastic philosophy, pleaded for a new system of education based on factual data and conclusions derivable from such data by strictly empirical and scientific methods.

John locke (1632–1704) used a psychological approach, his investigation of experience taking the form of an examination of consciousness. He held that what is known are ideas, and that the whole knowledge process consists in reflecting on the content of these ideas and in discerning their relationships. His empiricism, therefore, is primarily subjective. Locke had to assume a world of things with the power to cause sensible changes in a knowing subject. This world of things he reduced to a minimum of so-called primary qualities, viz, motion, rest, extension, magnitude, and number. Secondary qualities, for him, were the impressions made on the knower, viz, color, taste, sound, odor, resistance. Behind qualities there might be substance; but, since this was never directly sensed, the knowing subject could never account it as more than a collection of secondary sensible qualities. Locke thus thoroughly undermined the foundations of realism, and his successors were not slow to remove those foundations entirely.

George berkeley (1685–1753) concluded from this that, since man could never know things, but only ideas of things, there were no things at all. God could just as well cause the ideas of things within us as the things themselves.

In his own way, David hume (1711–76) was no less drastic. Never denying a reality independent of mind, he nonetheless reduced that reality to the barest minimum. Since the human intellect could make no contact with substance, the most that could be asserted was that there were ideas of events, and that these ideas were more or less vivid, more or less closely associated in the human mind. The mind itself was nothing more than a series of ideas, all following each other successively. Since only substance can exercise causality, he argued that causality could mean only a habitually constant association of ideas. This process led him to a hesitant skepticism about the validity of all knowledge.

American Development. In the United States the empirical movement developed chiefly under the influence of Charles Sanders peirce, William james, and John Dewey. Peirce (1839–1914) is generally considered the founder of pragmatism, a form of empiricism in which the emphasis is on activity. According to Peirce, the purpose of thought is to produce belief, and belief has three characteristics: (1) it is something of which man is aware; (2) it appeases the irritation of doubt; and (3) it involves man in establishing habits of action. Thus, beliefs are ordered to action, and different beliefs are distinguished by the diverse actions to which they lead. Hence, sensible effects become the criterion of the content value of any idea. Yet Peirce does attempt to account for abstract and class concepts. The concrete object of experience is for him an exemplification of the possible and as such is able to refer the knower beyond itself; this reference is not sufficient, however, to transcend the order of experience as a whole, and Peirce makes no attempt to do so.

With William James (1842–1930) a more radical form of empiricism appeared, affirming that the only way to settle metaphysical disputes is to refer them to action and practical consequences. James advocated a deemphasis of principles in favor of consequences and facts. He went further than Peirce in stating that its results not only give a proposition meaning, but even make it true. Hence, for him, truth is any activity that enables one to get into practical harmony with his experiential situation. In his preface to The Meaning of Truth (New York 1909), James describes his empiricism as consisting of (1) a postulate, (2) a statement of fact, and (3) a generalized conclusion. The postulate states that only those things that can be defined in terms drawn from experience should be debated by philosophers. The statement of fact is that the relations between things are as much part of experience as the things themselves. The conclusion is that the parts of experience are held together by relations that are themselves parts of experience. Thus does James reduce both knowledge and the object of knowledge to the flux of experience.

John Dewey (1859–1952) applied the teachings of Peirce and James to history, sociology, politics, and education. He taught that philosophy must grow out of the philosopher's personal experience in the cultural and historical situation in which he finds himself, this alone being of the real and constituting the real. Yet for Dewey such experience takes place in the naturalistic context of the 19th century, which accepted the Darwinian theory of evolution and regarded mind and man as climactic processes emerging out of the universal dynamism of nature. Experience, in his understanding, cannot be distinguished from nature, and reality is a series of events acting and reacting on one another on a purely physical level. In such a universe, truth is only a precarious balance of interconnecting events that constitute a situation, this situation being constantly modified from within and without. Natural science provides man with the most stable sort of knowledge possible. And faith becomes an act of trust and hope in science, in human intelligence, and in man's quest to unite himself ever more perfectly with the flow of events of which he is a part.

Critical Evaluation. Empiricism is forced to limit knowledge to the order of experience and to treat the human intellect simply as a more powerful sense faculty. Yet there is evidence, found in experience, that the intellect transcends the material order. Man does form class concepts, or universals; and, while sense experience may be needed in order to begin, the term of the process, the concept, is free from the limitations that matter everywhere imposes. A material thing is always individual, and so is a sensation. The intellect, however, forms concepts that are predicable of many different individuals in exactly the same way; such concepts abstract from individual differences and particularizations (see abstraction). Since the principle of particularity is matter, to be free from such limitation is to be free from matter (see individuation).

The fact of intellectual reflection also indicates that there is more to knowledge than what the senses provide. The intellect is aware of its own act as it places it, but the eye, for example, cannot see itself seeing. Intellectual reflection, too, can identify the principles that structure a sensible thing. There must be more than matter in a material thing; how else can the evident difference between one material thing and another be explained? Material things exist, yet existence and matter are not synonymous; otherwise how can thought that transcends the limitations of matter, but is just as real, be explained?

Empiricism emphasizes a truth without admitting its full implications. The need of experience in the knowing process must be recognized, but it must be recognized too that knowledge cannot be adequately explained merely in terms of the sensible. In fact, the human intellect finds in experience the need to transcend the sensible order and arrive at truths that alone make such experience intelligible.

See Also: knowledge; knowledge, theories of; phenomenalism.

Bibliography: f. c. copleston, Contemporary Philosophy (Westminster, Md. 1956). j. collins, A History of Modern European Philosophy (Milwaukee 1954). g. faggin, Enciclopedia filosofica (Venice-Rome 1957) 1:1878–94. É. h. gilson, Elements of Christian Philosophy (New York 1960). s. h. hodgson, The Metaphysic of Experience, 4 v. (New York 1898). g. p. klubertanz, The Philosophy of Human Nature (New York 1953). g. de santillana and e. zilsel, The Development of Rationalism and Empiricism (Chicago 1941). r. eisler, Wörterbuch der philosophischen Begriffe (Berlin 1927–30) 1:334–336.

[h. r. klocker]