In order to understand Hume’s concept of sympathy, we need to first clarify his usage of the term in the
Treatise. Let us recall Vitz’s distinction (Vitz 2016, 313-314):
(1) Hume uses the term ‘sympathy’ “to identify a psychological mechanism: namely, the principle of
sympathy, by which one ‘enters into’ the sentiment(s) of another.” He says that it is “the principle of
sympathy, by which we enter into the sentiments of the rich and poor, and partake of their pleasure and uneasiness” (T 2.2.5.14, SBN 362).
(2) He uses it “to identify a psychological process: namely, the sympathetic conversion of an idea of another’s sentiment into an impression of one’s own.” He says, “Sympathy … is nothing but the conversion of an idea into an impression by the force of imagination” (T 2.3.6.8, SBN 427). (3) He uses it “to identify the affective product of this conversion process: namely, the sentiment of
sympathy.” For instance, he says that a rich man’s possessions “produce an agreeable sympathy in us”
(T 3.3.5.5, SBN 616).
Although Hume’s uses of the term ‘sympathy’ is clearly distinguished in three different ways, Vitz raises a suspicion as to whether Hume himself recognizes this:
I do not mean to imply that Hume was aware of his varying uses of the term “sympathy.” In fact, I suspect that he was not and that his failure to distinguish clearly (perhaps, to notice) the varying ways in which he uses the term is one of the fundamental reasons that there is significant disagreement among Hume’s commentators about his account of sympathy. (Vitz 2016, 328)
Vitz’s interpretation is problematic in that the issue thereby addressed, that is, the problem of Hume’s confusing usage of the term ‘sympathy’ is merely superficial. The real reason why there is “significant disagreement among Hume’s commentators about his account of sympathy” is because they do not recognize the essential relation among these three uses of the term ‘sympathy’ (Vitz 2016, 315). For Hume, sympathy as a
“psychological process”, which Vitz introduces as a second use of the term ‘sympathy’, that is, “the sympathetic
conversion of an idea of another’s sentiment into an impression of one’s own,” is the key definition of
sympathy. And the other two uses of the term ‘sympathy’ revolve around it.
As we have seen in Chapter 1, the first use of the term ‘sympathy’ as a “psychological mechanism” is made up of two process:15
15“When any affection is infus’d by sympathy, it is at first known only by its effects, and by those external signs in the countenance and conversation, which convey an idea of it. This idea is presently converted into an impression, and acquires such a degree of force and vivacity, as to become the very passion itself, and produce an equal emotion, as any original affection” (T 2.1.11.3, SBN 317).
Process 1. We obtain an idea of the other's affection by making a causal inference, and then Process 2. We convert the idea of the other's affection into an experience of the affection itself.
The first stage is the psychological process to get an idea of the other’s affection by making a causal inference. The second stage is the psychological process to convert the idea into an impression, and this second stage exactly matches what Vitz introduces as a second use of the term ‘sympathy,’ that is, “the sympathetic
conversion of an idea of another’s sentiment into an impression of one’s own.” In my view, by the analysis of
the “psychological mechanism” of sympathy, what Hume wants to say is that the mechanism of sympathy, by which one ‘enters into’ the sentiment of another, involves two different psychological processes of making a causal inference and ‘sympathetic conversion,’ and that the work of the psychological process of ‘sympathetic conversion’ presupposes the cognitive process of making a ‘causal inference.’ From this, we can say that according to Hume, although we commonly regard the psychological mechanism, by which one ‘enters into’ the sentiment of another, as an unanalyzable and primitive one like an “emotional contagion”, it is actually analyzed as two different processes, and the real work of sympathy is confined to his second use of sympathy as a ‘psychological process’, that is, “the sympathetic conversion of an idea of another’s sentiment into an
impression of one’s own.” Thus, we can conclude that for Hume sympathy is mainly defined as the conversion of idea into an impression by imagination, and he technically uses the term “sympathy” as a ‘psychological mechanism’ in order to explain how the process of sympathy is generated.
Second, as Vitz points out, it is true that Hume also uses the term “sympathy” as referring to a kind of affection. Actually, we most commonly use the term “sympathy” this way in our everyday life. We say, “I feel sympathy for him” or “I send you my deepest sympathy”. Thus, Hume’s use of the term “sympathy” as a kind of affection itself is not problematic. The question is whether or not his different uses of the term “sympathy” cause any confusion for our understanding. Vitz’s answer is yes. As we have seen, he even suspects that Hume himself does not recognize his own different uses. I cannot agree with this view. An important point is that Hume defines ‘sympathy as an affection’ as “nothing but a lively idea converted into an impression” (T 2.2.9.13, SBN 385-386). Given that Hume makes a distinction between the vulgar system and the system of true philosophers, we can understand that the use of sympathy as an affection belongs to the vulgar system since this is our everyday unreflective usage and that the use of sympathy as a psychological process to convert an idea into an impression belongs to the system of true philosophers since it would give account of how to produce the sympathetic affection.
Thus, I would say that it is true that Hume uses the term ‘sympathy’ in three different ways, but these three uses are closely related and the key concept of sympathy as conversion process of an idea into an impression is central. If we catch the difference between Hume’s key concept of sympathy and the other two concepts of sympathy, we come to know that the difference between the uses are superficial. If so, we can ask a question. Why does he put this key concept of the conversion process of an idea into an impression at the centre of his understanding of sympathy? My answer is that the concept of sympathy as “the conversion of an idea into an impression” plays a pivotal role in bridging between the concept of “limited sympathy” and “extensive
sympathy”. According to him, we can sympathize not only with another person’s real feelings at present, called “limited sympathy”, but also with hypothetical ones of the person, called “extensive sympathy”:
’Tis certain, that sympathy is not always limited to the present moment, but that we often feel by communication the pains and pleasures of others, which are not in being, and which we only anticipate by the force of imagination. (T 2.2.9.13, SBN 385-386)
As Vitz points out, the psychological mechanism of sympathy allows us to enter into the sentiments of another, but this is only limited to the present sentiments. That is, the psychological mechanism of sympathy, which is introduced by Hume, does not give an account of all the phenomena of sympathizing with others. This is the reason why he puts not the psychological mechanism of sympathy but the process of converting an idea into an impress in the centre of his understanding of sympathy, I believe. Let’s see what he continues to say:
The bare mention of this is sufficient. Sympathy being nothing but a lively idea converted into an impression, ’tis evident, that, in considering the future possible or probable condition of any person, we may enter into it with so vivid a conception as to make it our own concern; and by that means be sensible of pains and pleasures, which neither belong to ourselves, nor at the present instant have any real existence. (T 2.2.9.13, SBN 385-386)
Thus, according to Hume, we don’t need to limit the work of sympathy only to sharing the real emotions of another at present. Rather, we can extend it to “pains and pleasures, which neither belong to ourselves, nor at the present instance have any real existence” since he defines that “Sympathy … is nothing but the conversion of an idea into an impression by the force of imagination” regardless of whether the idea is of a real emotion at present or of a hypothetical one (T 427, SBN 385-386).