Empiricism, Sensationalism, and Positivism

Thomas Hobbes (1588–1679)

• Believed all knowledge comes from sensory experience.

• Advocated physical monism—thoughts result from physical influences on the senses.

• Rejected free will, arguing that behavior is determined by appetites and aversions.

• Impact on psychology: Introduced a deterministic view of human nature and laid the groundwork for behaviorism by suggesting human actions follow predictable laws.

John Locke (1632–1704)

• Argued the mind is a blank slate (tabula rasa) at birth, with all knowledge coming from experience.

• Distinguished between primary (objective) and secondary (subjective) qualities.

• Impact on psychology: His emphasis on experience and learning influenced developmental psychology and empiricism.

George Berkeley (1685–1753)

• Denied the existence of material reality; all reality consists of perceptions.

• Believed perception exists because God perceives all things.

• Impact on psychology: His ideas anticipated later work on perception and subjective experience in psychology.

David Hume (1711–1776)

• Rejected innate knowledge, arguing knowledge comes from impressions and ideas.

• Introduced associationism—ideas are connected through resemblance, contiguity, and cause/effect.

• Questioned causality, suggesting it’s just a habit of mind.

• Impact on psychology: Laid the foundation for associationist theories of learning and cognitive psychology.

David Hartley (1705–1757)

• Proposed vibrations in the nerves as the basis for sensory experience.

• Developed an early theory of conditioned responses (precursor to classical conditioning).

• Impact on psychology: Pioneered ideas on learning and association, influencing behaviorism.

James Mill (1773–1836)

• Argued the mind is made of sensations and ideas connected by association.

• Saw thoughts as clusters of associated sensations.

• Impact on psychology: Developed a systematic account of associationism, influencing early experimental psychology.

John Stuart Mill (1806–1873)

• Expanded associationism with mental chemistry, where complex ideas emerge from simpler ones.

• Advocated a scientific study of the mind.

• Impact on psychology: His ideas helped push psychology toward becoming an empirical science.

Julien Offray de La Mettrie (1709–1751)

• Argued that humans are machines, with thoughts and emotions resulting from physical processes.

• Denied the existence of a soul or divine influence.

• Impact on psychology: Contributed to materialist psychology, influencing physiological psychology.

Auguste Comte (1789–1857)

• Founded positivism, arguing that knowledge should be based only on observable facts.

• Proposed the Law of Three Stages: societies move from theological to metaphysical to scientific explanations.

• Impact on psychology: Inspired early scientific approaches to psychology, leading to the rise of behaviorism and experimental methods.