The first section of Kant’s Groundwork of the Metaphysics of Morals opens with the sentence quoted above: one of the most-quoted sentences he ever wrote. What did he mean by “good without limitation”? what did he mean by “a good will”? and what is the significance of the concept in Kant’s ethics?

Good without limitation. Something’s goodness is limited when it depends upon external conditions. For example, medicine is good, though not if taken in a dose that is excessive, considering the age, weight or other condition of the patient. Wealth and power are good, though not in the hands of those who use them only for selfish purposes, or who use them for evil. Something is good without limitation, therefore, if it is good no matter what its external circumstances. It is good without limitation if it is good and cannot under any circumstances be bad.

What a good will is. To explain what a good will is it is necessary to explain what Kant meant by “good” and what he meant by “will”. “Good,” first, is a practical concept. This means that it has a necessary relation to action. Think of three stances, or points of view on the world. In one stance we are there to observe the world, in order to understand it. In another stance we are there to enjoy its affect on us, or to appreciate its beauty. In the remaining stance, which is practical, we view the world in order to act, in order to bring about something, or to prevent something from occurring. “Will” refers to what is called the mental faculty engaged in the practical stance. It differs from understanding and feeling, the faculties engaged for the other stances. The will is our general ability for causing something to happen (or preventing something from happening), intentionally. When we think of “a good will,” a will that is morally good, we refer to this ability as it is guided by our thought of the morality of what we are doing.

Significance of the concept. Kant begins the Groundwork with the concept of the good will in order to answer the question: How do we know that what we are doing is morally right or wrong? He does not doubt that we typically know this—the real question is how we know it. The first section of the book is an extended argument by analysis. By analyzing the concept of a good will, Kant will derive a simple formula that can tell us whether what we are doing is right. In the second section, this formula will be named “the categorical imperative.” Many a reader has gotten a mistaken idea from the first paragraphs of the Groundwork. They have exaggerated the significance of the good will, seeing it as the foundation of Kantian ethics (e.g., Harbison 1980, 59) – or its ultimate aim. As utilitarianism aims at bringing about happiness, it may be thought, so Kantian ethics aims at bringing about good will. In the first paragraphs of the Groundwork Kant does, after all, refer to the good will as the “the highest good.” But he later clarifies his use of that term, suggesting that a good will, or virtue, is only a component of the highest good (Kant 1997b, 92/5:110). Although it is true that his ethics recognizes an obligation to become a (more) virtuous person, this is but one obligation among many. Clarifying the principle that tells us what our various obligations are is more central to Kant’s purpose in the Groundwork. In order to be guided in action by the thought of the morality of what what we are doing, we need to know how we ought to act. Acting with a good will depends upon a moral principle for guidance, and the main point of the Groundwork is to search for and establish the supreme principle of morality.

Criticism. Is it true that a good will is good without limitation? Is it true that only a good will is good without limitation? Critics of Kantian ethics have answered each of these questions in the negative. The good will depends on adequate guidance in order to bring about what is good. But what if a person is misguided in acting? What if she thinks she is doing something good but in fact she is doing something wrong? The question is: Is it possible to do wrong with good will? There is no reason why Kant would have to deny this possibility (cf. Ross 1988, 7). He can say that a will’s goodness does not depend on the rightness of the action. Nothing he ever claimed implies that a good will always does what is right; any more than that every time someone does what is right she acts with a good will. It is a common mistake, especially among writers of introductory ethics textbooks, to assume that doing what is right, or what is your duty, requires acting with a good will, or acting with the right motive. Even philosophers who should know better sometimes make this mistake. Kant’s view on this point, according to Sidgwick, was that “duty, to be duty, must be done for duty’s sake” (1886, 260). Of course this leads to a contradiction, as shown by Ross (1988, 5-6), who also wrongly attributes the view to Kant. It is not a logical requirement for doing your duty that you do it for duty’s sake, or that you act with a good will. Kant never said that acting from duty is necessary for doing your duty. The second question was: Why think the good will is the only thing good without limitation, or the only thing that is good independent of anything external? G.E. Moore, for example, thought that beauty is intrinsically good, and that the enjoyment of beauty is intrinsically good (Moore 1903, §113). Kant would respond that beauty is not practical, so cannot be “good” in the sense of the term he used. He did not mean, of course, that beauty cannot or should not be enjoyed. But he would not agree that enjoyment of beauty should take precedence over morally right action. The way Kant saw it, the Good is one thing, the Beautiful is another (Kant 2000, 94-96/5:208-10). That response might adequately address a criticism based on Moore’s intuitions. But other critics have presented compelling arguments of a different sort on this point (see Gaut 1997, 165-70).

Controversy. So who has a good will? Does no one have a good will, simply because it is an ideal of perfect virtue? Do most of us have a good will (Dean 2006, 97), or only a few? Could it be that everyone has a good will? Kant never answered these questions; at least not with any clarity. The majority view is that a small percentage of us have good wills. Some people seem to care deeply about morality, and to be committed to doing what is right, even if it means sacrificing other things they care about: these people seem to have good wills. But they are rare. The perfectionist view says, on the contrary, that human beings can only approximate having a good will. The good will is here regarded as a humanly unachievable ideal of moral perfection (Louden 1986, 478). But those holding the universalist view disagree, insisting that everyone has a good will. This is because every human being is moved to some degree by the thought of doing what is good or morally right to do. Personally, I favor the universalist interpretation. Kant did write, once, that everyone has a good will, even the most corrupt (Kant 1998, 64/6:44). Some read a passage from the Groundwork similarly, where he seems to say that even a hardened scoundrel is conscious of having a good will (Kant 1997a, 59/4:455; see also Paton 1948, 169). Another reason supporting good-will universalism over the majority view concerns arbitrariness. It does not seem possible to draw any but an arbitrary line between those human beings who have a good will and those who do not (McCarty 2009, 220-30).