मानव के मन के अध्ययन के सन्दर्भ में, सत्य-असत्य की पहचान करने तथा समस्याओं के हल करने की मन की क्षमता को प्रज्ञा (intellect) कहते हैं। प्रज्ञा मन की वह क्षमता है जो सही निष्कर्ष पर पहुँचने में सहायक होती है।

In the study of the human mind, intellect is the ability of the human mind to reach correct conclusions about what is true and what is false in reality; and includes capacities such as reasoning, conceiving, judging, and relating. Translated from the Ancient Greek philosophical concept nous, intellect derived from the Latin intelligere, from which the term intelligence in the French and English languages is also derived. The discussion of intellect can be divided into two areas that concern the relation between intelligence and intellect.

• In classical philosophy and in medieval philosophy the intellect (nous) is the subject of the question: How do people know things? In Late Antiquity and in the Middle Ages, the intellect was the conceptual means of reconciling religious monotheism with philosophical or scientific study of Nature. This reconciliation made the intellect the conduit between the individual human soul, and the divine intellect of the cosmos. Aristotle first developed this with his distinction between the passive intellect and active intellect.

• In psychology and in neuroscience, the controversial Theory of Multiple Intelligences applies the terms intelligence (emotion) and intellect (mind) to describe how people understand the world and reality.