Lately great difficulty has been encountered in trying to establish acceptable moral theories that entail categorically binding moral judgements. Although the aim may not be to establish a theory that entails a categorically binding moral judgements, many of the feasable theories that have been developed prevent the possibility of categorically binding moral judgements. Moreover, proponents of theries that entail categorically bingin moral judgements are finding it increasingly difficult to withstand the onslaught of credible arguments attacking their Natural Law theories. Perhaps the most notable opponent is Hume whose Guillotine argument seems to have deflated the spirits of many moral realists. Other philosophers, like Moore, have followed suit adding to the number of attacks on Natural Law theories.

Hume fails to make one consideration that, when made, makes clear that his argument does not refute Natural Law theories. This consideration is made below and because it is made we discover that Hume’s argument provides support for categorically binding moral judgements very similar to Kant’s categorical imperative.

Hume points out that states of affairs can not lead to conclusions about what states of affairs ought to be. His assertion that the inference to an ‘ought’ statement from an ‘is’ statement is an invalid inference has carried substantial weight in attempting to make a moral judgement.

Hume proposes criteria for moral judgments that seem to result in the exclusion of categorically binding moral judgements. He proposes, as the reader may already know, that moral judgements about an agent’s actions must be made with consideration for the agent’s desires. In the Humean theory, states of affairs ought to be what the agent rationally desires. The Humean theory successfully establishes a basis for moral judgements without relying on the is-to-ought inference. We can only suggest that an action is right or wrong if we consider the agent’s desires. Obvious stipulations must be imposed, requiring that the desires are rational desire.

The reader may ask why we need to consider the agent’s desires when making a moral judgements. We find that we encounter difficulty when we try to provide that basis without subscribing to states of affairs. We find that theories that do not provide rational justification for their moral standards often result in self contradictory judgements, or the standard simply is unfounded and subscription to the theory disobeys rationality. When we consider an agent’s desires, we consider what the most rational course of action is, according to those desires. There are desires which may, themselves, be considered irrational for various reason and to attempt to find a suitable course of action based upon an irrational desire is not possible.

Alternately, an individual may have a completely rational desire, but the method the individual chooses in an attempt to fulfill that desire may entail steps that may be morally wrong (the may contradict other desires). For instance, a young boy may want to give his mother a gift (to make her happy) which we will consider a morally good thing to do without analysis. However, the boy chooses to shoplift the gift which is, arguably, a morally wrong thing to do (assume the boy understands this). The intent was certainly good, but the procedure was not.

We can conclude that a desire may be morally good – it is a rational desire – but this does not necessarily mean that any means of fulfilling that desire is morally good. Clearly some stipulations should be imposed on the formulation: The morally good action is the action that is based upon a rational desire and whose execution does not contradict another of the agent’s desires

It is unnecessary to investigate Hume’s argument in depth here, but if a review of Hume's’standpoint is required, the reader should refer to Hume’s Treatise of Human Nature Book III part I section 1.

We can see why Natural Law theories cannot work: iIf we try to establish an effective moral judgements we must support that judgement rationally. In essence the judgement must have a rational basis. We find that theories, like Divine Volunatarims, do not provide rational justification for their moral standards often result in self contradictory judgements, or the standard simply is unfounded and subscription to the theory disobeys rationality.

An objecttion may be made here by some purporters of Natural Law Theories: they may suggest that we can indeed make these inferences from states of affair to desirable states of affairs when moral theories exist independently of human opinions. More specifically, they may suggest that a divine commandment exists, that is, we can infer from an ‘is’ statement to an ought statement because a state of affairs, like a divine commandment, is what determines what we ought to do. Such contentions are founded on an incomplete or irrational basis. To suggest that moral standards have positive (independent) ontological status is an exercise in ontological promiscuity.

It appears that accteptable moral judgements are subjective: they are dependent upon an agent’s desires, rahter than a standard external to the agent. This is a false appearance.

It is here that the considreation is made that Hume left out: Hume has established that to act in accordance with a desire that has been determined as a rational desire is attributed the value of a morally good action. However, rational desires are harder to come by than we may think. In fact, we find that those desires that we ought to have are universal as a result of the requirements for rationality (non-self-defearing desires for example). What we find is that we may only rationally hold those desires that could be held universally as a desire. This seems conspicuously familiar. When we ask what we ought to desire we found the only suitable answer is similar to a Kantian assertion. Kant says

Similarly, the only rational desires we may hold are those desires that may be held universally. A particular desire that could not be held as a universal desire certainly cannot be rational. We are categorically bound to holding rational desires and are therefore categorically bound to holding desires that could be held as universal desires. Therefore there exist categorically bound moral judgements. We need to investigate this matter in more depth in order to be sure no mistake has been made.

It may be argued that there are circumstances where an individual may have a desire that should not be held universally but is appropriate for the situation. Let us consider the example where a prisoner of war is being held captive in a cage (as in Viet Nam). The prisoner may wish his captors were killed so that he could be freed. This is certainly an understandable desire and it may appear that this is a rational desire to hold in this circumstance. However, it certainly is not a desire that should be held universally. The fault occurs when the objector to the theory suggests that the valid desire is the desire for another person to be dead: the rational desire in this case is the desire to be free not the desire for the captor to be killed.

Now we may see that all of our rational desires are desires that could be held universally without encountering any conflicts. Any desire I have, then, could be held as a universal deire if it is to be esteemed morally good. Take my desire for a cup of coffee for example (for whatever rational reason - imagine I have to stay up late to write a philosophy paper). If this is a rational desire, the whole of humanity could then, desire a cup of coffee without presenting any moral dilemmas. I am not suggesting that because I want a cup of coffee the entire human race should want a cup of coffee. I am suggesting that the entire human race could want a cup of coffee, under any circumstances, and this desire could not be the cause of any moral contradictions. So, we are not categorically bound to wanting a cup of coffe because my desire for a cup of coffee is a rational desire. My wanting a cup of coffee is morally good, and any action I may take in order to aquire a cup of coffee is good as long as I do not contradict any of my other rational desires in the process. This must be true for any other desire of mine because if any particular desir is dependent upon circumstances it is not a rational desire.

We find that any objection that may be brought up to this mistakes an irrational desire for a rational desire.. For certainly, the desire to be free could be held as a universal desire, whereas the desire for another individual to be kill could not be held as a universal desire. The rational desire of the prisoner of war is the desire to be free.

Now it may be argued that I am making a definition here: objectors may claim that all that is being doe is redefining rational desires to limit rational desires to those desires that could be held universally without causeing any conflicting desires (an consequntly one cannot argue with a definition). This is not the case. Rational desires have not been redefined here; rational desires are those desire that are non-self contradictory, acylclic, and so on, which necessarily imposes the stipulation that rational desires may be held universally without difficulty. It has come as a consequence of being rational that a rational desire can be held universally without causing conflicts.

Now we can see that we are categorically bound to refrain from holding certain desires and must refrain from holding others. Because the list of rational desires we may hold is limited, it follows that there are certain categorically binding moral judgements. Killing may be considered morally bad because the desire to kill, under any circumstances, cannot be held as a universal desire; it is an irrational desire. It is the consequence of killing (in certain circumstances) that may be desired universally, as in the example of the prisoner of war.

What has been established should be clarified. There exist categorically bound moral judgements because

1. moral judgements require a rational basis
2. reference to present states of affairs cannot lead to conclusions about desirable states of affairs (or what ought to be the case)
3. it is the rational desires of an agent that determine morally right and morally wrong actions
4. the rational desires that an individual can hold are those desires that are non-self-contradictory, as stipulated by Hume; they are the desires that can be held as universal without yeilding moral dilemmas

The Humean theory has not been abandoned. The fact that there exist categorically binding moral judgements while supporting the humean theory comes about because when the question "What ought I desire" is asked, we find that we are bound to holding certain desires and must refrain from holding others. We find that there are categorically binding moral judgements are a necessary result of holding rational desires.