Epicureanism, founded by Greek philosopher Epicurus, emphasizes pleasure as the highest good. This ancient philosophy defines pleasure not as hedonistic indulgence, but as the absence of pain and mental disturbance, achieved through simple living and cultivating friendships. Epicurean thought is rooted in atomism and materialism, rejecting supernatural explanations. It promotes empiricism, self-sufficiency, and moderation in pursuing desires. The philosophy's legacy includes influencing scientific thought and ethical theories focused on well-being and happiness.