Associationism is a theory dating back to Plato and Aristotle that asserts that mental processes can be explained by the association of ideas. According to the theory, the mind is made up of ideas, commonly referred to as elements, that are categorized by means of their associations with one another.

Aristotle derived four laws of associationism: (1) The law of contiguity, which held that things occurring spatially or temporally close together become associated. For example, thinking of socks may lead to thinking about shoes; (2) The law of frequency stated that the more often two things are associated, or linked together, the more solid the association becomes; (3) The law of similarity asserted that when two things are similar, thinking about one will cause the individual to think of the other. Many people associate the fourth of July with fireworks, so thinking about fireworks would likely trigger thoughts of the fourth of July; and (4) The law of contrast asserted that thinking about one thing might trigger opposite thoughts. For example, thinking about how cold the weather is or watching snow fall might trigger thoughts of a beach vacation. Those laws were accepted as fact for roughly 2,000 years.

In the eighteenth century, David Hartley and James Mill re-popularized the tenets of associationism, modifying them a bit and stating just three laws: (1) The law of resemblance or similarity; (2) The law of contiguity; and (3) The law of cause and effect. The associationists proposed that ideas originated in experience, entering the mind through the senses and undergoing a variety of associative operations.

The philosopher John Locke (1632–1704) introduced the term “association of ideas” in the fourth edition of his Essay Concerning Human Understanding (1700), where he described it as detrimental to rational thought. George Berkeley (1685–1753), an Irish bishop, applied associationist principles to visual depth perception, arguing that the capacity to see things in three dimensions is the result of learning, not of innate ability. The British physician David Hartley (1705–1757) also dealt with the biological implications of associationism, formulating a neurophysiological theory about the transmission of ideas, and also describing physical activity in terms of association (a concept that anticipated subsequent principles of conditioning). Hartley also developed a comprehensive theory of associationism that encompassed memory, imagination, dreams, and morality. The Scottish philosopher David Hume (1711–1776) proposed the principles of similarity and contiguity, asserting that ideas that are similar or are experienced simultaneously or in rapid succession become associated with one other.

In addition to similarity and contiguity, other governing principles have been proposed to explain the means by which ideas become associated. These include temporal contiguity (ideas or sensations formed close together in time), repetition (ideas that occur together repeatedly), recency (associations formed recently are the easiest to remember), and vividness (the most vivid experiences form the strongest associative bonds). In the early twenty-first century, the school of psychology most similar to associationism is behaviorism, whose principles of conditioning are based on the association of responses to stimuli (and on association of those stimuli with positive or negative reinforcement). Also, akin to associationism, behaviorism emphasizes the effects of environment (nurture) over innate characteristics (nature). Association appears in other modern contexts as well: the free association of ideas is a basic technique in the theory and practice of psychoanalysis, and association plays a prominent role in cognitive theories of memory and learning.

See also Behaviorism ; Classical conditioning ; Nature-nurture controversy ; Operant conditioning .



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