---
title: Empiricism
section-id: epistemology
sort: 130
author: Prof. James Okafor
created: 2026-01-22 09:00
modified: 2026-02-27 10:00
language: en
description: The empiricist tradition and the claim that all knowledge derives ultimately from experience.
---

# Empiricism

Empiricism is the view that all knowledge derives ultimately from sensory experience. The British empiricists—Locke, Berkeley, and Hume—developed this position in opposition to the rationalists. Where the rationalists saw reason as the primary source of knowledge, the empiricists insisted that the mind begins empty and is furnished by experience.

## Locke’s Empiricism

John Locke’s *Essay Concerning Human Understanding* (1689) opens with a sustained attack on innate ideas. Locke’s positive view is that all our ideas—the materials of thought—derive from two sources: **sensation** (experience of the external world) and **reflection** (awareness of our own mental operations).

Locke distinguished **simple ideas**, which we receive passively from experience and cannot create or destroy, from **complex ideas**, which the mind builds by combining, comparing, and abstracting from simple ideas. The idea of red is simple; the idea of a red ball is complex.

This gives rise to a criterion for meaningfulness that recurs throughout empiricist philosophy: any genuine idea must be traceable back to the simple ideas from which it was built. Terms that cannot be so traced are, for Locke, empty or confused.

## Hume’s Empiricism

David Hume sharpened the empiricist program and pushed it to more radical conclusions. Hume distinguished **impressions** (immediate sensory or emotional experiences) from **ideas** (fainter copies of impressions preserved in memory and imagination). All genuine ideas must be copied from impressions.

Hume applied this as a test. Take any philosophical concept—causation, the self, moral obligation—and ask: from what impression is this idea derived? If no impression can be found, the concept is meaningless or confused.

Applied to **causation**, this yields a disturbing result. When we say A causes B, we seem to mean more than that A and B have always appeared together. We mean that A necessitates B. But Hume searched for an impression of this necessary connection and could not find one. We see A, then we see B, then we see A again and expect B again—but the necessity is nowhere in our experience. It is, Hume concluded, a projection of the mind, a habit of expectation created by repeated observation, not a feature of the world.

This **problem of induction** extends further. We believe the future will resemble the past because it always has. But this is circular reasoning: we are using induction to justify induction. Hume saw no rational justification for inductive inference. We cannot help making it—nature compels us to expect regularities—but we cannot rationally vindicate it.

## The Empiricist Criterion of Meaning

The logical positivists of the twentieth century developed Hume’s approach into the **verification principle**: a statement is meaningful only if it is either analytic (true by definition) or empirically verifiable. Metaphysical claims—about God, the soul, objective values, ultimate reality—are not analytic and cannot be verified, so they are, strictly speaking, meaningless.

The verification principle proved self-undermining. Is the principle itself analytic? It does not seem so. Is it empirically verifiable? Not obviously. If it fails its own test, it seems to be meaningless by its own standard. This problem, and the difficulty of specifying what counts as ‘verifiable,’ eventually led to the decline of logical positivism.

## Empiricism and Science

Despite the difficulties, empiricism has deeply shaped the philosophy of science. The idea that scientific theories must ultimately answer to observation and experiment—that no theory is immune to empirical disconfirmation—is a broadly empiricist commitment. Karl Popper’s criterion of **falsifiability** is a sophisticated empiricist response to the problem of demarcating science from non-science.

Quine’s ‘naturalistic epistemology’ takes empiricism in a different direction. Rather than seeking a priori foundations for knowledge, Quine proposes that epistemology be continuous with natural science. We study how human beings, as physical organisms, acquire knowledge, using the same methods we use to study any other natural phenomenon.

## Summary

- Empiricism holds that all knowledge derives from experience
- Locke grounded all ideas in sensation and reflection; complex ideas are built from simple ones
- Hume’s copy principle and the problem of induction are the most influential products of the empiricist tradition
- The verification principle of the logical positivists attempted to operationalise empiricism but proved self-defeating
- Empiricism continues to shape the philosophy of science and naturalistic approaches to epistemology
