idea

An idea is a mental representation or object of thought that can serve as the basis for reasoning, planning, or creative activity. It may be a concept, a proposed explanation, an envisioned action, or a belief about how something might be. Ideas can be simple or complex, and they may be formed, revised, debated, or tested through experience and evidence.

Etymology and usage: The term idea derives from Latin idea, via the Greek idea (eidos), meaning form or shape. In English, it has long been used to describe both a mental image and a proposal or principle.

Types and processes: Ideas range from abstract notions such as justice or beauty to practical plans, hypotheses, and inventions. The generation of ideas—ideation—is central to creativity and problem solving, often involving observation, analogy, abstraction, and iterative testing.

Impact and context: Ideas influence science, philosophy, culture, and technology. They spread through communication, undergo refinement or rejection in light of evidence, and can initiate movements or innovations. An idea, in short, is a mental construction with potential to guide action and understanding.