This article focuses on the relationship between morality and law through the debate between William Whewell (1794-1866) and John Stuart Mill (1806-1873), two important moral philosophers of 19th century Britain. Whewell belongs to a tradition maintaining that the basic moral principles can be known intuitively through an inherent faculty such as moral sense or conscience. In the meantime, Whewell argues that the process of knowing these basic principles intuitively is not an irrational process and that the reason is active throughout (...) the whole process of knowing. In this context, the reason is the most basic concept of Whewell's system. In Whewell's system, the will of God is the highest/ultimate good. Relatedly, action in accordance with the will of God is morally right action. On the other hand, utilitarianism, to which Mill belongs, is a moral theory that determines the greatest happiness of the highest number of people as the criterion for morally right action. This theory does not include any metaphysical and theological elements, which argues that morality should be based on experience and introspection. Utilitarianism rejects the claim that there are basic moral principles that can be intuitively known. This approach of utilitarianism makes these two theories natural opponents of each other. One of the topics of the Whewell-Mill debate is the juncture of morality and law. In this context, Whewell's views on the moral-law relationship, Mill's criticism of Whewell on this issue and Whewell's responses to Mill constitute the subject of the article. The main purpose of this study, in which the comparative method is adopted, is to gain new perspectives on the relationship between morality and law. When we focus on the Whewell-Mill debate, we see that Whewell deals with the moral-law relationship on the basis of the concept of right, while Mill deals with the concept of justice. According to Whewell, it is impossible to talk about morality unless there are rights determined by law. In this regard, justice basically means compliance with the law. Like Whewell, Mill accepts that justice is not static but dynamic, and argues that only the utility can determine what just is. Mill objects to Whewell's views on three main criticial points. These are; according to Mill, Whewell first makes law the basis of morality by claiming that it is not possible to talk about morality where there are no laws. Whewell, objecting to this criticism of Mill, states that he does not make law the basis of morality; he says that he needs law to put moral principles into the practice. The second criticism of Mill is that Whewell makes laws the criterion of moral righteousness, which narrows morality down to rights and therefore to law compliance. Whewell objects to Mill, saying that moral rightness is much broader concept than legal rightness. For him, obedience to the law is only part of moral righteousness. Mill’s last criticism is that Whewell made obedience to the law a moral duty, even if it is not just. In Whewell's system, obedience to laws confirming slavery is made a moral duty. Whewell, on the other hand, admits that laws may be immoral from time to time, but states that obedience to these laws is more reasonable than disobeying them; because the problems that will arise from non-compliance with the laws are much greater. What needs to be done is to make sure that more just laws are legislated. However, according to Whewell, legislation is the duty of the jurist, not the moralist. These criticisms made by Mill against Whewell are actually criticisms that is related Mill's own system. Mill neither himself can give satisfactory answers to these criticisms. In conclusion, in the polemic between Whewell and Mill, it is possible to find other different answers of both thinkers regarding the relationship between morality and law. However, it cannot be said that these answers completely solved the problems stated above. (shrink)