David Hume's Philosophy: Empiricism, Reason, and Human Nature

Hume's Science of Man: Foundation and Purpose

David Hume defends the dependence of all sciences on the science of man, or the science of human nature. It is man who comprehends these sciences, which are his own creation, and it is man who must be studied. This Science of Man aims to guide society toward a world free of prejudice and religious bigotry, moving away from ancient and superstitious beliefs.

Critique of Superstition and Metaphysics

Hume, a profound rationalist, believes that rationalist superstition and metaphysics form the ideological basis of societal shortcomings. Religious intolerance, hypocrisy, and malice impede the progress, culture, and welfare of society. The Science of Man, Hume argues, intends to liberate humanity and dismantle misleading philosophy and false wisdom. To establish a robust science of man, the permanence and uniformity of human nature across time and space are essential. This uniformity allows for the derivation of laws governing human conduct and the study of humanity. Human nature remains consistent across all times and places, though not all individuals act in the same way under identical circumstances. Experience and observation are the foundation of the science of human nature, and it is through them that knowledge must be sought. The ultimate essence of human nature, however, lies beyond the limits set by experience.

Hume's Empiricism: Experience, Impressions, and Ideas

For Hume, experience is a collection of observations drawn from daily life, history, and society. To grasp the empiricist criterion of meaning, Hume distinguishes between impressions and ideas.

Distinguishing Impressions from Ideas

Impressions are received with strength and vividness, consisting of sensations, passions, and emotions. Impressions can be categorized as:

• Sensations: Entering our consciousness through external senses.
• Reflections: Arising from our internal nature.

Sometimes, an impression can even be awakened by an idea. For Hume, ideas are terms used in the mind without their corresponding immediate impressions.

Relations of Ideas vs. Matters of Fact

According to Hume, all our knowledge is categorized into either relations of ideas or matters of fact.

• Relations of Ideas: These truths belong to mathematics and are known intuitively through the mere comparison of ideas. For knowledge and truth in this type of relationship, the human mind relies on its understanding of these ideas. They express necessary truths, where their negation implies a contradiction. The verification of such truths occurs independently of experience, meaning they are known a priori.
• Matters of Fact: These truths pertain to the natural sciences. Denying a matter of fact does not imply a contradiction. The only way to prove their truth is through experience, meaning they are known a posteriori.

Challenging Traditional Metaphysics

Through his philosophy, Hume denies the existence of general ideas, asserting that what is real is the impression, and every impression is particular. He rejects the traditional metaphysical notion of substance, arguing that it is not given to us through sensation and thus lacks reality.

Hume's View on Personal Identity

Hume also criticizes the concept of personal identity, which Descartes conceived as an entirely spiritual, simple, and foundational self. Hume believes that the self is based on the relation of cause and effect, constantly connecting and amending all our perceptions.

The Problem of Induction and Human Reason

Regarding the problem of induction, Hume explains that if predictive knowledge comes from experience, and the expression "the future is in conformity with the past" also depends on experience, then we are reasoning in a circle. Psychologically, Hume posits that the belief that the future will conform to the past is a habit formed by experience itself. Hume emphasizes that his philosophical analysis of induction does not suggest that reasoning leads us to suppose the past is similar to the future, or to expect similar effects from similar causes, as rational metaphysics might claim. Instead, he argues that induction has its own experiential and logical way of proceeding, completely independent of deductive reasoning.

Hume's Three Degrees of Reason

Within reason, Hume distinguishes three degrees:

• Knowledge: Security arising from the comparison of ideas.
• Proof: Arguments derived from the relation of cause and effect, which are free from doubt.
• Probability: Evidence still accompanied by uncertainty.

Hume's Four Sciences for Human Progress

Hume stresses that all the knowledge humanity needs to progress is contained within four sciences:

• Logic
• Morality
• Arts and Literary Criticism
• Politics