"On Love" is a philosophical treatise that explores the complexities of romantic love, breaking it down into various forms and stages. The work delves into the psychological processes involved in love, introducing the concept of "crystallisation," where lovers project idealized qualities onto their beloved, enhancing their affection. The treatise categorizes love into types such as "passion-love," "gallant love," "physical love," and "vanity-love," providing a nuanced understanding of how love manifests in different forms. The author uses both historical examples and personal anecdotes to analyze the phenomenon, offering a methodical and theoretical framework for understanding the birth and progression of love. Early chapters reflect on the stages of admiration and hope, while emphasizing the transformative process of crystallisation, wherein affection is shaped by imagination rather than reality. Through this lens, Stendhal explores the interplay between the real and the imagined in romantic relationships, providing a deeper understanding of human affection. This treatise offers a profound, analytical perspective on the nature of love and its psychological dimensions.