Empiricism: Locke, Berkeley, and Hume
George Berkeley: Empiricism
Concept
Berkeley equates the sensible world with reality and denies the intelligible. He rejects general ideas but accepts abstract ideas. Abstraction is unnecessary because things are what they are in themselves. Qualities are the only reality, perceived by the mind as ideas, and God facilitates this perception. General ideas form when the mind disregards the specific circumstances of a concrete idea, allowing it to refer to particulars. Ultimately, Berkeley’s philosophy is metaphysically immaterialist, denying the corporeal world and affirming the existence of spiritual substance (God and the soul).
David Hume: Empiricism
Concept
Hume posits that perceptions are the substance of our minds. Perceptions encompass everything the mind can remember, whether derived from the senses or reflection. He divides perceptions into:
1. Impressions
These are immediate perceptions and differ in the force with which they affect the mind (e.g., feeling cold). Classes of impressions include:
- Impressions of Sensation: Derived from our senses (e.g., seeing color).
- Impressions of Reflection: Relate to mental states (e.g., fear of the dark).
- Simple Impressions: Cannot be further separated (e.g., the acidic, orange flavor).
- Complex Impressions: Can be broken down into simpler perceptions (e.g., an orange: round + acidity + color).
2. Ideas
These are mediate perceptions and are copies of impressions (e.g., remembering the cold I felt).
Relationship Between Ideas and Types of Knowledge
Hume identifies a force in nature that connects ideas based on three principles: similarity, contiguity in space and time, and causality. These principles give rise to different types of knowledge:
- Relations of Ideas: Governed by the principle of similarity. This knowledge is a priori and does not originate from experience (e.g., mathematics). It is necessary because its denial would be contradictory.
- Matters of Fact: Governed by the principle of causality. This knowledge is a posteriori and originates from experience (e.g., physics). It is contingent, and its denial is possible.
Knowledge of Facts and the Law of Cause and Effect
Critique of the Principle of Causality
Rationalists considered causality a self-evident principle of reason. Descartes believed knowledge stemmed from God, who established this principle. Locke accepted this principle to justify the existence of God and external reality. Hume argued that all such arguments are based on cause and effect. For him, the idea of causality implies a necessary connection between an event and its consequence, leading to the expectation that the second event will necessarily follow. Hume believed that habit influences our minds; when we observe A, we expect B. He discarded intuition and reasoning as justifications for causality, considering them circular. He used the phrase “the future will be like the past” (absolute determinism) as an example. Hume argued that this is an unprovable assumption; natural events are always contingent, making knowledge contingent as well, contrary to the rationalist view.
Phenomenalism and Hume’s Skepticism
Hume’s focus on impressions as the basis of knowledge leads to radical phenomenalism, where reality is reduced to pure phenomena. This results in uncertainty about knowledge and a tempered skepticism, guided by common sense and reflection to combat dogmatic claims to truth.
Features of Empiricism
- Rejects innate ideas.
- Establishes the validity of the sensible world.
- Rejects knowledge unrelated to experience.
- Denies the possibility of universally valid science.
Rationalism vs. Empiricism
Innatism
Rationalists argue for innate ideas not acquired through senses or experience, while empiricists reject nativism, locating the origin of ideas in sensory perceptions.
Mathematicism
Rationalists use mathematics as a model but not for interpreting reality. Empiricists use mathematics to interpret reality and gain knowledge.
Similarities
Both rationalists and empiricists seek knowledge to improve the human condition, validate human intelligence, and advance science. Rationalism uses deductive reasoning from rational truths to apply experience correctly, while empiricism uses inductive reasoning from experience to reach generalizations. Empiricism proposes a new concept of reason limited by experience, deeming metaphysics impossible.
John Locke: The Theory of Knowledge
Ideas
To know is to perceive ideas in the mind. Ideas are intermediaries between the thing (the sensible world) and the mind, and this intermediation is abstraction.
Origin and Classes of Ideas
Locke denies innate ideas, asserting that all ideas come from experience. He categorizes ideas as follows:
1. Simple Ideas
- Of Sensation: Derived from external experience (passive understanding). These include:
- Primary Qualities: Perceived by more than one sense and are the same for everyone.
- Secondary Qualities: Perceived by only one sense and vary between individuals.
- Of Reflection: Ideas the mind has of its own actions (active understanding).
2. Complex Ideas
- Substance: A concept with two definitions:
- As a support.
- As a substrate or the set of qualities that make a thing what it is, its essence.
The concept of substance should not be confused with the idea of substance (e.g., Rose = name + set of attributes).
- Mode: Qualities of the substance, without subsistence on their own.
- Relation: Comparison of two ideas based on their relationship, combining the concepts of substance and mode.
3. General Ideas
Created to represent the similarity of many individuals.
Knowledge and its Classes: Self, God, and Reality
Locke distinguishes three types of knowledge based on the relationship between ideas:
- Intuitive Knowledge: Immediate and certain knowledge of the self, linked to our existence.
- Demonstrative Knowledge: Mediate knowledge requiring a series of proofs, used to demonstrate God’s existence as a creative cause.
- Sensitive Knowledge: Refers to the external physical world and material objects.