Pratyaksa is a key concept in Hindu philosophy that refers to direct perception or empirical observation, serving as one of the primary means of knowledge acquisition. It emphasizes the importance of sensory experience in understanding reality and is often contrasted with other forms of knowledge, such as inference and testimony. In the context of logic and epistemology, pratyaksa is crucial for establishing the validity of knowledge claims and plays a significant role in the Nyaya school of thought.