Philosophy of the Modern Age

The Crisis of Empiricism in the Philosophy of G. Berkeley and D. Hume

It so happened that in England, where the development of science since Bacon had relied upon empiricism and sensationalism, a situation arose in which empiricism encountered a crisis manifested in the proliferation of subjective idealism and skepticism. The former was represented by George Berkeley, while the latter was embodied by David Hume.

George Berkeley (1685 - 1753) was born in southern Ireland and was the eldest of six children in a minor landed gentry family. He attended the same school as the renowned writer Jonathan Swift. At the age of fifteen, he became a student at the college in Dublin, where he also began teaching in 1707. In 1709, he published the work “A New Theory of Vision,” which bore a philosophical nuance, and in 1710, he released his principal theoretical treatise, “A Treatise Concerning the Principles of Human Knowledge.” The ideas of this book were later presented in a more popular format in a work known in abbreviated form as “Three Dialogues between Hylas and Philonous.” Starting in 1713, Berkeley embarked on various travels, visiting London, Italy, and France, and in 1728, he traveled to America with the dream of founding a college in the Bermuda Islands. This venture proved unsuccessful, and Berkeley returned home after three years. In 1734, he became a bishop.

In “A Treatise Concerning the Principles of Human Knowledge,” Berkeley set himself the task of refuting atheism and its theoretical foundation—materialism—drawing on sensationalism. Materialism asserts that abstract concepts such as substance and matter correspond to a reality that exists independently of human consciousness. In Berkeley's view, “substance” and “matter” are nonexistent entities, and the words that express them are mere errors of consciousness (here, he somewhat aligns with nominalism). The objects of our knowledge are ideas rather than some external things. Berkeley defines ideas as sensations; objects or things are nothing more than stable combinations of sensations. We perceive ideas, and any idea is merely a singular sensation. What people refer to as things is simply complexes of sensations.

Berkeley places particular emphasis on the meaning of the term "to exist." When someone asserts that matter exists, that substance exists, that a person or a horse exists, Berkeley suggests that one should first clarify the meanings of these expressions and pose the question, “What does it mean to exist?” The philosopher himself offers this response: to exist means to be perceived. From this premise follow very perilous consequences for the philosopher himself. It follows that a particular thing exists as long as I or someone else perceives it. The relentless progression of reasoning in this direction leads to subjective idealism and even to solipsism, wherein only my consciousness is acknowledged as real, while everything else is but its creation. Berkeley found himself compelled to balance between subjective and objective idealism to avoid accusations of solipsism. For instance, what can I say about the table at which I am currently sitting: does it exist? Yes, the table exists because I perceive it, and what I call a table is a complex of my sensory impressions. But if I leave the room, does the table continue to exist in that room, given that I am no longer there? Berkeley urges strict adherence to the meaning of the term "to exist" and advises responding thus: the table exists in the sense that when I return to the room, I will perceive it; but while I am absent, its existence remains problematic for me. But what if we consider it independently of me? Does the table or anything else exist regardless of my presence, as someone enters and leaves the room? Berkeley would respond that if I am not there, then there are others who perceive it, and if they are absent as well, ultimately the absolute perceiving subject is God. By acknowledging God, the philosopher thus shifts to the position of objective idealism.

Berkeley's doctrine revealed the weaknesses of empiricism and sensationalism, especially as represented by Locke, in which the subject is a passive entity subject solely to the influence of the external world. Berkeley recognized not only the secondary qualities of objects (colors, tastes, etc.) as subjective—as Locke did—but also primary qualities, such as size, motion, and shape. Berkeleyan motifs occasionally re-emerge in philosophy on new foundations, while their refutation often teeters on the brink of mere faith in the reality of the external world, for it is challenging to counter them with purely logical arguments. The French Enlightenment thinker Denis Diderot once remarked about Berkeley’s philosophy: “An extravagant system, which, in my view, could only have been devised by the blind! And this system, to the shame of human reason, to the disgrace of philosophy, is the most difficult to refute, although it is more absurd than any other.”

David Hume (1711 - 1776) was born in Edinburgh, Scotland, into a family of lawyers. His father died early, and the future philosopher was raised by his mother, a woman of remarkable character. At the age of twelve, Hume enrolled at the University of Edinburgh, after which he worked as a librarian and spent some time in public (diplomatic) service. His first philosophical work, “A Treatise of Human Nature,” was written in 1738. As the philosopher himself noted, “the treatise was published stillborn, not even deserving the honor of inciting the complaints of fanatics.” Later, when Hume gained greater recognition for his historical works, he revised the first book and published “An Enquiry Concerning Human Understanding” in 1751.

In his initial epistemological position, Hume is also a sensationalist, but in answering the question of what causes our sensations, he significantly differs from Locke. Hume does not accept either a materialist or a subjectively idealist stance. His position is this: whether the external world exists as the cause of our sensations or not cannot be proven. Our minds deal only with the content of sensations, not with the causes behind them. Our perceptions convey as little about the existence of an external world as they do about its nonexistence. Hume writes: “By what argument can we prove that the perceptions of the mind must be produced by external objects, entirely distinct from those perceptions..., and cannot be caused either by the activity of the mind itself, or by the suggestion of some invisible and unknown spirit, or by some other cause even more unknown to us?” How then can this question be resolved? “Certainly,” Hume continues, “through experience, as with all similar questions. But at this point, experience is silent and cannot help but remain silent.”

At the same time, Hume acknowledges that people, as slaves to their natural instincts, always consider the images arising from their senses to be external objects. Individuals do not even contemplate that these images are merely representations of sensory perceptions. This unyielding instinctive belief lacks any rational justification.

Hume frequently appeals to experience, using this term extensively. However, he entirely excludes external objects from the concept of "experience." By refusing to acknowledge, and thus to know, the object, Hume reduces the task of philosophy to the investigation of sensations and perceptions and the clarification of the relationships that arise between them in human consciousness.

Hume sees no distinction between primary and secondary qualities (recalling Locke, who considered the former objective and the latter subjective); for him, both are subjective. He designates the entire primary content of consciousness with the term "perception." Having completely dismissed the question of objective reality, he focuses on the quantitative differences in the intensity and vivacity of perceptions. Thus, Hume differentiates between immediate, vivid, and strong perceptions or impressions and the fainter, weaker secondary perceptions or ideas.

Following Locke, Hume categorizes impressions into sensory perceptions and self-perceptions. Examples of the former include sight, hearing, touch, and temperature. Examples of the latter encompass affects and emotions: pleasure and displeasure, love and hate, fear and hope. Furthermore, Hume distinguishes between simple perceptions (e.g., "red") and complex perceptions (e.g., "apple"). The entire content of consciousness and all human knowledge is constructed from such impressions and ideas. The mind itself adds nothing to this material; it merely organizes and combines impressions. Hume then explores the connections between different ideas.

Ideas are not copies of the external world but rather of the immediate, direct impressions. Ideas are linked by three principles of association: resemblance, contiguity, and causation. All these principles are not innate, nor a priori, but derived from experience. If we recall that Hume understands experience subjectively, merely as a collection of sensations, then spatial, temporal, and causal connections are not considered inherent to the objects themselves; they are simply the result of habitual associations of perceptions.

Hume denies the existence of a material substance underlying mental acts, but he also does not allow for a spiritual substance. What is termed the "self" merely represents a bundle of perceptions, transiently connected.

To substantiate the possibility of knowledge and establish a criterion for the reliability of human judgments, Hume refers to everyday experience and the natural instinct inherent in people. Guided by this instinct, individuals believe in the reality of the world surrounding them and rely on this belief in their actions.

Everything that thought engages with, Hume divides into two classes: the relations of ideas and facts. The former includes propositions of geometry, algebra, etc., which do not depend on experience and are products of pure thought. The latter, namely facts, lack certainty and obviousness. Their truth cannot be demonstrated through logical means, as is the case with the former.

Through such reasoning, Hume arrives at skepticism regarding the possibility of reliable knowledge of the world. "The most perfect philosophy of nature," he writes, "only pushes the boundaries of our ignorance a little further, while the most refined moral or metaphysical philosophy merely helps us uncover new realms of it. Thus, the conviction of human blindness and weakness is the result of all philosophy."

Consistently adhering to skepticism, Hume adopts a skeptical position regarding the existence of God, advocating for deism. However, he does not entirely reject religion, deeming it necessary to preserve religious morality for the common people. His religious skepticism pertains only to the enlightened social elite. Hume's skepticism served as a foundation for French Enlightenment thinkers, and he is regarded as the first Enlightenment figure of the Modern Age.