Diderot Effect

The Diderot effect is a social phenomenon related to consumer goods which either posits that form culturally defines groups that are considered cohesive or refers to a process of spiralling consumption resulting from dissatisfaction induced by a new possession. The term was coined by anthropologist and scholar of consumption patterns Grant McCracken in 1988, and is named after the French philosopher Denis Diderot (1713–84) who first described the effect in an essay.

The term has subsequently come to be used, especially in discussions of sustainable consumption or green consumerism to refer to the process whereby a purchase or gift creates dissatisfaction with existing possessions and environment, provoking a potentially spiralling pattern of consumption with negative environmental, psychological and social impacts.

The effect was first described in Diderot's essay "Regrets on Parting with My Old Dressing Gown". Here he tells how the gift of a beautiful scarlet dressing gown leads to unexpected results, eventually plunging him into debt. Initially pleased with the gift, Diderot came to rue his new garment. Compared to his elegant new dressing gown, the rest of his possessions began to seem tawdry and he became dissatisfied that they did not live up to the elegance and style of his new possession. He replaced his old straw chair, for example, with an armchair covered in Moroccan leather; his old desk was replaced with an expensive new writing table; his formerly beloved prints were replaced with more costly prints, and so on. “I was absolute master of my old dressing gown,” Diderot writes, “but I have become a slave to my new one … Beware of the contamination of sudden wealth. The poor man may take his ease without thinking of appearances, but the rich man is always under a strain.”

In McCracken's usage the Diderot Effect is the result of the interaction between objects within "product complements", or "Diderot unities", and consumers. A Diderot unity is a group of objects that are considered to be culturally complementary in relation to one another. For example, items of clothing, furniture, vehicles, etc. McCracken describes that a consumer is less likely to veer from a preferred Diderot unity in order to strive towards unity in appearance and representation of one's social role. However, it can also mean that if an object that is somehow deviant from the preferred Diderot unity is acquired, it may have the effect of causing the consumer to start subscribing to a completely different Diderot unity.

Sociologist and economist Juliet Schor uses the term in her best selling 1992 book the 'The Overspent American: Why We Want What We Don't Need' to describe processes of competitive, status-conscious consumption driven by dissatisfaction. Schor's 2005 essay "Learning Diderot’s Lesson: Stopping the Upward Creep of Desire" describes the effect in contemporary consumer culture in the context of its negative environmental consequences.