I. Introduction
Upon first inspection, Hume and Kant show very different accounts for the role of reason in their moral thinking. Hume puts reason secondary after sentiments in the formation of morality, while Kant devotes all his ink into establishing a moral system almost entirely based on reason[1]. In this paper, I will first examine how the two philosophers see the role of reason, and the differences between their moral systems that arise from their conceptions of reason. Then, I will attempt to show that the contrast in their views on the role of reason may not be as sheer as one conceives it to be.
II. Role of reason in Humean and Kantian context
1. Humean reason and morality
In the Treatise, Hume claims that reason only has two roles, “either when it excites a passion by informing us of the existence of something which is a proper object of it; or when it discovers the connexion of causes and effects, so as to afford us means of exerting any passion.” (T459), which is to say that reason can 1) reveal the existence of certain facts, only to excite passion and 2) instrumentally discover certain means to achieve the ends of passion. Reason does not cause us to act—moral sentiments do. To make a moral judgment is to detect, by means of a sentiment, the operation of a virtuous or vicious quality of mind. The sentiment here is a peculiar kind of feeling—a feeling of approval (love, pride) or disapproval (hatred, humility). We call the traits that elicit our approval “virtues[2]”, and those that elicit our disapproval “vices”.
So far, Hume’s claims base morality in sentiments. However, in the Enquiry, Hume introduces the concept of utility as a concrete measurement of one’s moral worth. Though one may argue that one has to use reason extensively to learn the utility of various traits, utility and disutility are merely means; were we indifferent to the weal and woe of mankind, we would feel equally indifferent to the traits that promote those ends. Therefore, overall it is still in sentiments that Hume’s moral system is grounded.
2. Kant’s reason and Kant’s morality
Kant seems like the polar opposite of Hume. Kant thinks that the practical purpose of reason is to produce a good will, which is a will that acts for the sake of the moral laws themselves. And reason, separate from all empirical experience, can determine the moral laws according to which all ends can be determined as moral. These principles of moral reason are known as the categorical imperative[3], which says that “act only according to that maxim by which you can at the same time will that it should become a universal law”. To see how a universal law is derived rationally, let us look at Kant’s perfect and imperfect duties[4]. Perfect duties are derived from contradiction in thoughts. One example Kant gave for perfect duty is that one should not give lying promises, for if everyone gives lying promises, the concepts of promises would lose their meaning and no longer exist, producing a contradiction in our thoughts that assumed the existence of promises. Imperfect duties are derived from contradiction in will. For example, helping others in need will be an imperfect duty, because rationally nobody is willing to choose a world in which no one lends a helping hand.
As we can see from these examples, Kant’s moral principles may be described as purely rational, irrelevant to human nature and local custom, or emotional sensitivity. Additionally, note that Kant’s moral principles are valid for all rational beings, and that only rational thoughts can be described as moral: for Kant, only the one who is consciously cognizing duties is truly acting for the sake of duties, and only deliberately good action can be moral.
3. Difference between the two moral systems
As we have seen, Hume and Kant derive moral rules from different origins, namely sentiments and rationality. Due to this difference, the same actions can be deemed as immoral by one philosopher, but not the other. Take the example of lying to an adversary, say a murderer. It is plausible that Hume would approve a lie to a murderer, because 1) it is our natural human inclination towards survival that justifies this lie 2) the motive of the will to lie in this circumstance can easily be approved and understood by everyone 3) the utility of survival is arguably greater than the utility of honesty. Kant, on the other hand, had openly argued that even in this circumstance, lying is immoral, given that we have previously derived with reason that a universal principle forbids lying.
This example notwithstanding, lots of moral rules that can be derived in Hume’s system of morals can also be derived in Kant’s—what makes this example different? The deep-rooted discrepancy comes not only from the difference of their account of the role of reason, but the role of circumstance too-- Kant’s categorical imperatives such as “no lying” are morally binding because they derive from a process that involves only reason, without involving any circumstantial contingency. Adding in circumstances could not change the result of derivation. In Hume’s case, the utility of a circumstance, the sentiments raised, and the moral judgment made can be circumstantial and dynamic, and it is largely dependent on the particularity of humanity. In this case, the utility and sentiments of lying is evaluated as against human lives, producing a completely different conclusion from Kant.
III. Reconciliation between Kant’s and Hume’s view on role of reason:
Though in this short essay it cannot be thoroughly argued that the any moral systems share fundamental similarities, it perhaps can be shown that the incongruency between Hume and Kant’s views on the role of reason is not as huge as we think.
Firstly, the reason why the role of reason in Hume’s moral system is so diminished, is that Hume thinks that reason alone cannot produce any action. However, Kant does not think that reason directly produces action either, because there is a missing piece between reasons alone and actions, which is the conscious recognition of how the reasoning produces the action. This consciousness ensures that that one follows moral duties for the sake of following moral duties. To say that Kant thinks reason leads to action directly is a misinterpretation. Suppose one understands that lying is bad, because one understands precisely how this universal maxim is derived, but one never lies only because one considers the possibility of getting caught greater than not. In Kant’s opinion, his honesty is not considered moral---his reason and his action is disconnected. What’s missing is a conscious recognition of moral duty that is derived from reason. In this example, it is the act of referring to the moral rule when deciding not to lie. To summarize, though Hume’s reason does not directly produce action, Kant’s reason does not either. Humean reason produces passion, which produces moral actions; Kantian reason produces a conscious cognition to follow that duty, which produces moral action.
Secondly, in Kant moral system, it is not necessary for the agent to be emotionally inclined towards the action for him to be moral, he simply has to act for the sake of his duty, which is a universal maxim. However, the evaluation of universality of imperfect duties cannot be devoid of a human sentiment. Take helping others in need as an example. Suppose a robot follows Kant’s logical evaluation and use only logic to try to produce a contradiction to support helping others in need. The robot will get stuck when it tries to see what is wrong with a world where nobody helps others in need. Kant answers that “a will that resolved on this [5]would conflict with itself, since the case could sometimes arise in which he needs the love and sympathetic participation of others”. For this evaluation to be completed, it is not enough to have a robotic rationality and computational power, but rather one has to be human and understand why a world where nobody helps each other is undesirable. Though Kant’s moral system is based on reason, it is only to the extent that the evaluation of universality takes on a logical form. Behind this form, the evaluation process is considerate of sentiments and humanity, similar to Hume. That should not come as a surprise to us, because the fundamental similarities shared by the two moral systems comes from that both rationality and sentiment are rooted in humanity. Kant simply takes it for granted that humanity is also part of the rational agents without stating it explicitly.
IV. Conclusion
In this paper, I have attempted to minimize the difference between Hume and Kant on their thoughts of the role of reason by showing that Kant also needs a medium between reason and action, and that Kant’s the derivation of morals laws is not complete devoid of sentiments. Of course, this is not to deny the differences between two moral systems, but rather to say that these differences do not come from the distinct roles of reason like how it seems at the first glance. They may come from the difference between the goals of these two moral systems. For Hume, the goal is to have a realistic and human system based on which we can evaluate virtues and vices and increase happiness and utility. For Kant, morality is a binding set of rules that provides rational beings with the exclusive means to freedom. Future research can be devoted into a better understanding of this difference.
Reference
Kant, Immanuel. Groundwork for the Metaphysics of Morals. Oxford Uni Press, 2019.
Hume, David. An Enquiry Concerning Human Understanding. Enc. Britannica, 1952.
Hume, David, et al. A Treatise of Human Nature. Oxford University Press, 2014.
[1] In this paper, “reason” stands for “practical reason”.
[2] There are some virtues that are natural, and some virtues that are artificial, such as justice.
[3] Three alternative formulations of the Categorical Imperatives: 1) that of universalizability 2) to treat humanity as an end in itself 3) recognize the right of others to act autonomously
[4] Here, “duty” is the synonym of “moral law”.
[5] “this” as in, preferring this world to another world where people do help each other in needs
Comments