Empiricism vs. Rationalism: Locke, Hume, and the Nature of Knowledge

Empiricism vs. Rationalism

Empiricism is a philosophical stream arising from Anglo-Saxon philosophers, almost simultaneously with rationalism. Leading representatives are British: Locke, Berkeley, and Hume. Empiricism argues that all knowledge comes from experience.

Empiricism accepts some basic ideas of rationalism. For both empiricists and rationalists, the being of things is given in consciousness, not the external world. There is no access to the things themselves, but to the ideas we create in our minds about those things. There are some ideas that both empiricists and rationalists agree on:

  • Both built their philosophy from consciousness. Awareness is important, compared to external reality.
  • The two streams claim that knowledge is knowledge of ideas. We know things, but only the ideas about them.
  • The two streams are of great importance to the theory of knowledge (apart from empiricists’ contributions to ethics and politics).
  • The two streams are of great importance to science.

However, the two currents oppose each other on a number of key issues:

  • For an empiricist, experience is the only source of knowledge, unlike the rationalists, who base knowledge on innate ideas.
  • For empiricists, there are no innate ideas. When we are born, our minds are like a tabula rasa (blank slate).
  • The scientific model to follow for empiricists is the physical sciences, not mathematics, as it is for the rationalists.
  • For the empiricists, the practical application of knowledge is essential. Rationalists remain in the abstract, while the empiricists will apply their theories to politics, morality, etc. Empiricists are great defenders of human freedom and democracy.
  • Empiricists critically examine metaphysical concepts such as the idea of substance and causation, which still prevailed among the rationalists.

Rationalism: The senses deceive us. We cannot trust them; they do not give reliable knowledge. Innate ideas, my conscience, and my mind are the only reliable sources of knowledge.

Empiricism: You only know what your senses perceive, i.e., what you see here and now. Everything that is not “here and now” is not knowledge but faith, religion, or imagination.

Both streams will face an impasse that can only be resolved with the philosophy of Kant.

John Locke

Knowledge

Locke begins his theory by criticizing the existence of innate ideas. There are people who lack these ideas. These ideas are not in their minds. The mind is like a blank paper at birth, emptied of characters. Through sensory experience, we acquire knowledge.

There are two sources from which knowledge comes: sensations and reflections. Sensations are all the information that comes from the senses. They are the main source of ideas. Reflection is the perception of the operations of our minds, such as thinking and reasoning. (See Essay Concerning Human Understanding) Therefore, all knowledge comes from experience, and we cannot have knowledge beyond it.

Human reason has the ability to combine and relate what it perceives.

With sensation and reflection, simple ideas are displayed in our minds. But from these, we can create more complex ideas. Among the complex ideas, Locke cites the ideas of causality and substance.

Politics

Locke argues against Aristotle’s theory that society is natural. Instead, he proposes that society is created democratically by humans. For him, the state of nature is more positive than that of Hobbes (which involves fighting and war). Locke reflects on a hypothetical state of nature, a state prior to society. In that state of nature, Locke argues, individuals have two characteristics:

  • They are free to organize their actions and dispose of their possessions in accordance with natural law.
  • They are equal, having equal rights, rights that we have in our nature, such as private property. According to Locke, there are some rights that already exist in nature.

Between Hobbes and Locke, the difference lies in their views of the state of nature versus society. For both Hobbes and Locke, the rupture between the two is reinforced.

To ensure these characteristics, the state emerges as a rational way to continue the evolution of these rights. A sound contract is needed to move from the state of nature to the formation of a civil society. (See Two Treatises of Government)

When the state is created, citizens freely decide to give up certain rights to the legislative and executive branches to preserve freedom, equality, and private property. The aims of the state are:

  • Safeguard private property.
  • Resolve disputes that arise.
  • Apply justice.
  • Achieve peace, security, and the common good.

Locke defends liberalism and individual rights. He criticized absolutism and defended a division of the three branches of government (executive, legislative, and judicial) to prevent any possibility of corruption and degeneration. The king is subject to the three branches, and the people must be sovereign.

One of the most important aspects of the state is tolerance. Wars and conflicts are due to intolerance, especially religious intolerance. Thus, Locke opposes the use of religion as an instrument of power. Prosecuting those who are contrary to the Christian faith is anti-Christian because God does not force us to profess a religion, but merely proposes it. If a person ignores what the true religion is, the solution cannot be violence, but freedom of conscience. Belonging to a religion is something free and voluntary. However, Locke recognizes the importance of accepting the existence of God for social harmony and believes that Christianity is dying of rationality. Either way, the state must undoubtedly respect religious freedom. (See A Letter Concerning Toleration)

David Hume

Knowledge

With his philosophy, Hume seeks to know the limits of human knowledge. He analyzes knowledge based on the concept of perception. Perceptions are all the contents of the mind. All perception comes from experience; Locke says that there are no innate ideas. You cannot go beyond experience. There are two kinds of perceptions: impressions and ideas.

Impressions are straightforward; they are the images that our senses capture from the outside world. They are provided prior to ideas.

Ideas are indirect; they are the images that impressions leave in our minds when we remember them.

Both ideas and impressions can be simple or complex. Complex ones are the result of combining several simple ones. The mind connects different ideas, usually according to a series of laws, such as the law of similarity (when you think of an idea, it leads to another similar thing), the law of contiguity, and the law of causality.

For Hume, there are two kinds of knowledge: matters of fact and relations of ideas. Relations of ideas belong to the insights and demonstrations of science. Their truth does not depend on whether the figures or numbers exist; Hume has to accept this.

Matters of fact are a kind of knowledge that we can access through sensory experience; they are reasonings about the physical world. They are not necessary; they can be otherwise.

The problem is that our minds are never satisfied and tend to create more and more complex ideas, referring to the future (e.g., when a billiard ball collides with another, our minds automatically create a new idea, which becomes the idea of causality, and anticipates reality). Therefore, what we usually call knowledge is nothing more than anticipations of reality created by habit or custom. Hume calls these types of ideas beliefs. (See A Treatise of Human Nature)

With this theory, Hume will develop one of the harshest criticisms of Western philosophy:

  • He criticizes the concept of causality.
  • He criticizes the idea of substance. There is no impression that can correspond to substance. If we remove the empirical characteristics, there is nothing left. Substance is nothing more than a collection of simple ideas that we name to group this collection, which we unite with our imagination.
  • He criticizes the rationality of the concept of “self.” It is a belief under which we group multiple perceptions.
  • He criticizes the existence of God. Its existence cannot be proven rationally. There is no rational basis for religion. He is very critical of religion, considering it superstition and fanaticism, particularly Catholicism, and asserts that the clerics are taking advantage of the ignorance of the faithful. The foundation of religion is not rational or moral, but instinctual. Humans turn to religion because of the fear and anguish caused by their inability to control natural occurrences. He prefers monotheistic religions to polytheistic ones because he considers them more tolerant.

Hume defends a skeptical philosophy, stating that the only true knowledge is that which the senses give us here and now. We can only consider information as current empirical knowledge. Any additional data that our senses give us are nothing more than beliefs. It is a radical and impactful stance. Hume bases his entire philosophy on the senses.

Morality

Morality: The ideas that a person has about good and evil.

Ethics: The philosophical reflection on why something is right or wrong.

Most philosophers say that ethics is based on reason. For Hume, reason cannot be the basis of morality. Morality has no rational basis. While other philosophers argued that moral reason should dominate over passions, Hume says it is the reverse. Reason is focused on discovering truth or falsity, while morality focuses on the approval or disapproval of moral actions.

What is the criterion we use to approve or disapprove an action? Those who argue that morality should dominate reason think that it is ideas that make us approve or disapprove an action. However, for Hume, what makes us approve or disapprove an action is whether we feel it is fair or not. It is therefore the sense that an action gives us pleasure, or is useful to us, or the contrary, that it causes us pain or is useless to us. We associate a moral action with what we find pleasant or unpleasant.

Moral principles are not innate. They come from experience. This theory is called “moral emotivism” because it defends emotions and feelings as the foundation of morality. Feelings are related to the beliefs or convictions that each person has.

Hume develops the naturalistic fallacy in his work. Through experience, we know the events that occur in reality. We show how things are, not how they should be. But facts are not moral judgments. For Hume, moral judgments are not knowledge. Moral judgments cannot rely on experience because they refer to what should be, not what is. They are derived from feelings and emotions. For Hume, there is no connection between the natural order that exists (what is) and the moral order (what should be). Such a connection is a fallacy, which has been the basis throughout the history of ethics.

Hume thinks that because of the naturalistic fallacy, we often use descriptive phrases (rational) and evaluative statements (moral). This involves an illogical, irrational leap. (See An Enquiry Concerning the Principles of Morals)