He developed a theory for the freedom of the will in his De Libertate Arbitrii (On Freedom of Choice) somewhat different from that of Augustine (De Libero Arbitrio), in that he combined two of Augustine's senses into one. These are theories on the freedom of the will and not compatibilist notions that we call "freedom of action" or Isaiah Berlin calls "negative freedom."

It is convenient to refer to them by Mortimer Adler's three kinds of freedom. In The Idea of Freedom, vol.I, Adler classifies all freedoms into three categories:

• The Circumstantial Freedom of Self-Realization
• The Acquired Freedom of Self-Perfection
• The Natural Freedom of Self-Determination

The freedom we have identified as circumstantial is variously called "economic freedom," "political freedom," "civil liberty," "individual freedom," "the freedom of man in society," "freedom in relation to the state," and "external freedom." It is sometimes referred to negatively as "freedom from coercion or restraint," "freedom from restrictions," or "freedom from law," and sometimes positively as "freedom of action," "freedom of spontaneity," or "freedom under law."

(The Idea of Freedom, vol I, p.127)

The Acquired Freedom of Self-perfection is the idea from Plato to Anselm to Kant that we are only free when our decisions are for reasons and we are not slaves to our passions (making moral choices rather than satisfying desires).

This is the acquired or learned knowledge to distinguish right from wrong, good from evil, true from false, etc. Anselm calls this libertas, in which man is only free when following a divine moral law. Sinners, says Anselm, do not have this kind of free will, which is odd because sinners are presumably responsible for evil in the world despite an omniscient and omnipotent God.

Instead, Anselm says that those who have the ability (posse) to sin or not to sin have what he calls liberum arbitrium, this is the ability to choose from among alternative possibilities, some of which may include self interest.

For Anselm, thanks to God's grace, only God and the angels have pure libertas.

Anselm cites the example of an agent who is given the choice to lie or to die. Shall he do the right thing and tell the truth, in which case he dies, or do what is in his self-interest and lie? Compare Robert Kane's example of the businesswoman who has to choose between aiding a victim in an alley or going on to her business meeting.

This is Adler's Natural Freedom of Self-Determination.

According to G. Stanley Kane, Anselm combines libertas and liberum arbitrium. This makes sense, because pure freedom (libertas) is to live a perfect life in God's grace, whereas a more normal sense of free will (liberum arbitrium) involves judgment, decisions between alternatives (including moral decisions).

In order to simplify reference to these two notions of freedom, I will call the first notion explained above the freedom of self-perfection and the second the freedom of choice.56 Both these notions of freedom are found in Augustine's later writings, where they are generally, though not invariably, referred to respectively by the terms "libertas" and "liberum arbitrium."57 Contrary to the practice of Augustine and many others throughout the Middle Ages, Anselm does not make this distinction between liberum arbitrium and libertas, for his single definition encompasses both these types of freedom.

To understand how the single definition can be made to stand for such diverse realities as the freedom of self-perfection and the freedom of choice, we must realize that freedom as Anselm defines it (the ability to keep justice) is not as such exactly identical with either of these but will under certain circumstances assume the form of one while under other circumstances it will assume the form of the other. In other words, freedom as Anselm defines it is a determinable which will under different circumstances assume different determinate forms. In any determinate form of freedom there are elements which are not essential to freedom as such though they are essential to that determinate form of freedom.

The word in Anselm's definition which is the key to its significance as a single formula covering both kinds of freedom is "ability" (potestas). The freedom of self-perfection is a determinate form of generic freedom in that it is the ability never to do anything unjust; that is to say, it is the ability to do what is just but under certain conditions—conditions where it is impossible to do anything unjust. Similarly, the freedom of self-determination is also a determinate form of generic freedom because it too is the ability to do what is just, but here it is found under conditions where it must be possible also to do what is unjust instead.

Hence neither the state of self-perfection as such nor the power of choice as such is essential to freedom as such as Anselm conceives it. Freedom, therefore, is not definable as the state of perfection or the power of choice. One might infer from this that there could conceivably be individuals who have neither attained the state of self-perfection nor possess the power of choice but who are nevertheless free. Such people, it might be thought, would possess the ability to do what is just but under conditions which are different from those characteristic of the freedom of self-perfection and the freedom of choice. But this would be a mistake. For the respective defining conditions of the freedom of self-perfection and the freedom of choice are mutually exclusive and exhaustive. If a person has the ability to do what is just, then either he is able to do what is unjust instead or he is not. There is no other possibility.

The simplicity of Anselm's definition tends to hide its remarkable richness. A number of major factors are brought together coherently in a single conception: the ultimate end of rational life, self-determination, moral responsibility, sinless perfection, and choice between moral alternatives. The definition makes explicit the orientation of free will to the ultimate end of rational life, namely, justice. A person can be just in performing an act only if he is self-determined in doing so. Freedom, then, entails self-determination. Self-determination, in turn, is both necessary and sufficient for moral responsibility. Self-determination, therefore, is found in every being that has the obligation to be just, i.e., every being that is free. The power of choice between alternatives, however, is present only in some of the beings who are free, namely, created beings. But it is found in all created beings who are free, for it is the only form which self-determination can take, and the only power by which justice can be achieved, under the conditions of creaturehood. A created being cannot choose what is just in a self-determined way if he cannot also choose what is unjust instead. Hence, while freedom as such is not to be defined in terms of the power of choice between moral alternatives, in human beings the only form which freedom can take is the ability to choose between moral alternatives. Similarly for God: while freedom as such is not to be defined in terms of the inability to do anything not just, the only form which freedom can take in God is the inability to do anything not just.

Probably the greatest significance of Anselm's definition is that it enables him to do something which has not been successfully done by any other major Christian thinker, namely, to unify under a single concept the two major ideas of freedom in the Christian tradition—ideas that had heretofore been held distinct and had appeared so divergent. What appears at first glance, then, to be a rather narrow definition of freedom turns out upon examination to be remarkably inclusive in its compass.

The two traditions of freedom have often been recognized and noted.58 But I have nowhere found a full appreciation of the manner in which Anselm combines them in his single conception of freedom. Most of his commentators have interpreted his doctrine as a freedom of self-perfection," though there are some who have recognized elements of the freedom of choice in his thinking." There are some even who criticize him for making no room in his theory for moral choice." And finally, there are some who think that he fails to see clearly the distinction between the two major kinds of freedom.

The only one that I have been able to find who sees something of the way in which Anselm incorporates both traditions in his theory is Mortimer Adler. He writes that "Anselm does not sharply distinguish between the two freedoms but instead distinguishes diverse modes of the will's freedom by reference in this life to its possession or lack of rectitude accompanied by the constant power to retain or lose rectitude when possessed, but not to regain it when lost."" Adler thus sees that Anselm brings together both notions, but he is unclear on the way they are brought together. For he speaks of the freedom of self-perfection and the freedom of choice as two "aspects" of one freedom. This is a mistaken account of the relation between the ge- neric freedom of Anselm's definition and the two determinate forms. Self-perfection and choice are not aspects of freedom, but freedom actually is self-perfection when an individual possesses rectitude and cannot lose it, and freedom actually is the power to keep rectitude as a matter of moral choice when an individual possesses rectitude and can lose it. Rather than being aspects of the same power, self-perfection and the power of choice are forms that this power takes under different circumstances.

The answer to this, I think, is clear. Freedom is conceived by Anselm more narrowly than the will. While freedom in rational creatures makes it necessary for them to have the ability to will what is unjust as well as what is just, freedom is not to be straightforwardly identified with the power of choice, whereas the will is (in creatures). Freedom, under whatever form it is found, is essentially and only the power to keep justice.

This means that freedom in these created beings can be identified with the affection for justice, and with the instrument and its acts insofar as they are governed by the affection for justice, but whatever else is found in the will-- the affection for happiness, and the instrument and its acts insofar as they are governed by it—is not a part of freedom. This holds even in those who have achieved confirmation in rectitude. For even though their affection for happiness has been brought into perfect subjection to the affection for justice, the two affections are still different and still directed toward different formal objects. Consequently, freedom does not include the ability to will happiness or beneficial things.

This distinction between freedom and will breaks down when we come to the case of God, but then every distinction breaks down in the case of God, since he is a simple unity without any real diversity of parts or attributes." The case of God, then, cannot be taken as indicating the relation between will and freedom on any lower level.

It may be thought that the conclusion here, that freedom is not identical with the power to choose as such, contradicts the earlier conclusion that in rational creatures freedom takes the form of the power of choice. There is no inconsistency, however, for the statement that freedom takes the form of the ability to choose means that freedom is the ability to keep justice as a matter of choice. As such, it is still the power to keep justice, and it is only that. In this it is like freedom generally. The way it differs from the other form of freedom is that in this form justice can be kept only by being willed as a matter of choice. The power of choice includes the ability to will something sinful as well as what is just, but the ability to will justice through this kind of choice does not.

Here again the doctrine of the affections illumines the issue. Justice can be willed only through the affection for justice, whether or not there is some other choice which can be made instead. If there is another choice which can be made, it must be willed through another affection. The power of choice, then, is the ability to choose whether one shall will in accordance with the affection for justice when one could have chosen in accordance with the other affection instead. In other words, when there is a possibility of moral choice, the capacity of the will for willing justice exists alongside of another capacity, the capacity for willing happiness. But this does not mean that the capacity for willing justice is or includes the capacity for willing happiness. The will includes both, but the affection or capacity for willing justice does not.

If this is correct, then V. J. Bourke is mistaken when he says that in Anselm's view the will is "in the genus of libertas."65 What this phrase means is not entirely clear, but at the very least it must mean that freedom is the wider and more encompassing concept than will. Besides the arguments just given, Anselm's dictum, "All power follows the will,"66 also seems inconsistent with this account. Since freedom is a particular kind of power, it then follows, or depends upon, the will. Moreover, Anselm's doctrine that the animals are endowed with will but do not have freedom also militates against Bourke's view. The cumulative force of all this evidence is hard to resist. It is difficult to deny that Anselm held that the will is the general power of willing, while freedom is one specific kind of power of willing, namely the power of willing justice.