Turing Test

A test of a machine's ability to exhibit intelligent behavior equivalent to, or indistinguishable from, that of a human.

How it works

Proposed by Alan Turing in 1950, the test involves a human interrogator having text conversations with two participants — one human, one machine — without knowing which is which. If the interrogator cannot reliably identify the machine, the machine is said to have passed the Turing Test. Turing proposed it as an operational definition of machine intelligence, avoiding the philosophical question of whether a machine can 'truly think.'

Why it matters

The Turing Test defined the field of AI's aspirational goal for over 70 years and introduced the concept of evaluating AI by its conversational behaviour rather than its internal mechanisms. Modern LLMs routinely pass basic versions of the test, prompting debate about whether the test is still meaningful as a benchmark. It remains culturally significant and philosophically important in discussions about machine consciousness, personhood, and what we mean when we say a machine is 'intelligent.'