In his book The Moral Molecule, Paul Zak claims that oxytocin plays a decisive role in shaping human behavior. He argues that philosophical explanations of morality are mere philosophical speculation, as moral behavior can be fully explained from a biological perspective by relying solely on oxytocin. This study, employing a descriptive-analytical method, critically examines this idea. First, it demonstrates that oxytocin, as a hormone, does not have a direct and complete causal effect on moral behavior, contrary to Zak's claims. Second, it explores evidence showing that oxytocin, in addition to promoting empathetic behaviors, can also lead to emotions such as jealousy and schadenfreude. Third, it presents findings suggesting that the effects attributed to oxytocin might result from reduced anxiety and increased social motivation rather than the direct creation of complex moral behaviors. Finally, this study argues that even if oxytocin induces empathetic behaviors, such behaviors are not always ethical. Morality requires considering principles beyond empathy, such as fairness and justice. Consequently, this paper critiques the notion of oxytocin as the "moral molecule," emphasizing the complexities of moral explanations and the necessity for more comprehensive approaches.