Cleanthes’ Two Illustrative Analogies in Part 3 of Hume’s Dialogues. 

Abstract 

In Part 2 of David Hume’s Dialogues Concerning Natural Religion, Cleanthes presents the analogical Argument from Design, through which he attempts to prove that there are sufficient resemblances between the design of the world and the design of machines to countenance the conclusion that the cause of the design of the world resembles human intelligence. Philo puts forth several criticisms of Cleanthes’ argument, none of which moves Cleanthes to reject the Design Argument. In Part 3, Cleanthes urges that Philo’s reluctance to accept the Design Argument is due to his prejudice against arguments supporting religion, and that, therefore, Philo’s criticisms ought to be refuted “by illustrations, examples, and instances, rather than by serious argument and philosophy”. In this regard, Cleanthes puts forth two illustrations - the Articulate Voice speaking from the clouds, and the Living Vegetable Library. In this paper, I attempt to understand why Cleanthes chooses these two illustrations to try to convince Philo of the Design Argument, and I evaluate each of these illustrations in terms of their potential to unprejudice Philo in regard to the analogical Argument from Design.[1]

Keywords: Analogy, Irregular Arguments, Articulate Voice, Vegetable Library 

Introduction  

In Part 2 of David Hume’s Dialogues Concerning Natural Religion, Cleanthes defends the analogical Argument from Design - the argument which purports to prove that the similarities between the design of the world and the design of machines in terms of means to ends relations and a coherence of parts lead to the conclusion that the cause of the design of the world resembles human intelligence, “though possessed of much larger faculties, proportioned to the grandeur of the work, which he has executed” (D.109). 

Look round the world: Contemplate the whole and every part of it: You will find it to be nothing but one great machine, subdivided into an infinite number of lesser machines, which again admit of subdivisions, to a degree beyond what human senses and faculties can trace and explain. All these various machines, and even their most minute parts, are adjusted to each other with an accuracy, which ravished into admiration all men, who have ever contemplated them. The curious adapting of means to ends relations, throughout all nature, resembles exactly, though it much exceeds, the productions of human contrivance; of human design, thought, wisdom, and intelligence. Since therefore the effects resemble each other, we are led to infer, by all the rules of analogy, that the causes also resemble; and that the Author of Nature is somewhat similar to the mind of man; though possessed of much larger faculties, proportioned to the grandeur of the work, which he has executed. By this argument a posteriori, and by this argument alone, do we prove at once the existence of a Deity, and his similarity to human mind and intelligence. (D.109) 

It is clear from what Cleanthes presents in this argument, that he regards the world to be a machine, the defining features of which are (1) the universal adaptation of means to ends relations, and (2) the coherence of parts of all the machines which comprise the design of the world. In other words, purposive design is evident throughout the design of machines and throughout the design of the world.   

Philo undertakes a series of criticisms of Cleanthes’ Design Argument in Part 2, centering around what he regards to be the proper use of the principle “like effects prove like causes”. He insists that the proper use of this principle requires that we observe an object of one type constantly conjoined with an object of another type, whereupon observing a new case of either type of object, we can infer, by analogy, the existence of the second type of object. The resemblances between the objects previously observed and the object(s) under consideration must be sufficient to enable us to classify the objects under consideration as objects of those types respectively. Philo insists that the design of the world does not bear an adequate resemblance to any machine with which we are familiar to enable us to classify the world as a machine of that type. Accordingly, he urges that the principle ‘like effects prove like causes’ cannot be applied to the case under consideration, namely, the design of the world and an intelligent cause of design: 

         When two species of objects have always been observed to be conjoined together, I can infer by custom, the existence of one, whenever I see the existence of the other. And this I call an argument from experience. But how this argument can have place, where the objects, as in the present case, are single, individual, without parallel, or specific resemblance, may be difficult to explain. And will any man tell me with a serious countenance, that an orderly universe must arise from some thought and art, like the human; because we have experience of it? To ascertain this reasoning, it were requisite, that we had experience of the origin of worlds; and it is not sufficient surely, that we have seen ships and cities arise from human art and contrivance… (D. 115) 

      Cleanthes takes a different approach to the proper use of the principle “like effects prove like causes”. Consider the following passage spoken by Cleanthes as a reaction to Philo’s claim that the universe does not bear a specific resemblance to any kind of object in the world:  

It would surely be very ill received, replied Cleanthes; and I should be deservedly blamed and detested, did I allow, that the proofs of a Deity amounted to no more than a guess or conjecture. But is the whole adjustment of means to ends in a house and in the universe so slight a resemblance? The economy of final causes? The order, proportion, and arrangement of every part? (D.110) 

In this passage, Cleanthes does not directly address the issue raised by Philo, namely, that the design of the world does not bear a specific resemblance to a particular kind of object in the world, which would countenance classifying the world as an additional object of that type. Rather, in his response, Cleanthes focuses on purposive design throughout the design of the world and machines. Cleanthes regards these resemblances as sufficient to apply the principle “like effects prove like causes” to the design of the world and to the design of machines. Philo’s objection about the reasoning in the Argument from Design, that we are dealing with objects –the world and God - that are “single, individual, without parallel, or specific resemblance” (D. 115) would not move Cleanthes because, as we now understand, Cleanthes does not hold to Philo’s view that to apply the principle “like effects prove like causes”, we must find objects of one type constantly conjoined with objects of another type. Cleanthes insists that purposive design is present throughout the design of the world and in the design of machines; and this is sufficient to enable us to conclude that the world is a machine. And, since machines have intelligent causes of design, we are able to conclude, using the principle 'like effects prove like causes', that the design of the world has an intelligent cause of design. While Cleanthes, at least tacitly, agrees that the design of the world does not enable us to classify the world as a machine of a particular kind (the world does not resemble a house, a ship, etc.), he does hold that purposive design throughout the design of the world and the design of machines does enable us to classify the world as a machine. Therefore, the observed conjunction involves machines or objects whose essential design involves means to ends relations and a coherence of parts, and intelligence as their cause. In other words, Cleanthes focuses exclusively on the purposive design in machines and the world in arguing that the design of the world resembles the design of machines. 

No resolution of the disagreement between Philo and Cleanthes on the proper use of the principle ‘like effects prove like causes’ occurs in Part 2, and, therefore, no conclusion is reached in Part 2 by the disputants regarding the acceptability or unacceptability of the Design Argument. 

The Illustrative Analogies in Part 3 

Having clarified the respective positions of Philo and Cleanthes on the proper use of the             principle, ‘like effects prove like causes', I now turn to the two illustrative analogies presented by Cleanthes in Part 3. When Cleanthes speaks in the opening paragraph of Part 3, he emphasizes that there is no need to prove the similarity of the design of the world to the design of machines, “because this similarity is self-evident and undeniable. The same matter, a like form: What more is requisite to show an analogy between their causes, and to ascertain the origin of all things from a divine purpose and intention?” (D.117) When Cleanthes presented his version of the Argument from Design in Part 2, he argued that there is resemblance in the design of all natural objects in virtue of means to ends relations and a coherence of parts (purposive design), and that the world is, in effect, the totality of these various machines. Now, in Part 3, Cleanthes maintains that, because the similarity between the design of the world and machines is self-evident, he should undertake to refute Philo’s objections through “illustrations, examples, and instances, rather than by serious argument and philosophy” (D. 117). Putting these points together, we should expect that Cleanthes will present illustrations exhibiting purposive design which would lead us to conclude, through the principle “like effects prove like causes”, that the cause of the design of these objects is intelligence. It is also clear that, given that Cleanthes is speaking of all natural objects in the Argument from Design, the illustrations that he employs in his attempt to convince Philo should not be additional actual or real natural objects: necessarily, therefore, he must have recourse to constructed or imaginary objects.

I begin with the Articulate Voice heard from the clouds:  

Suppose, therefore, that an articulate voice were heard in the clouds, much louder and more melodious than any which human art could ever reach: Suppose, that this voice were extended in the same instant over all nations, and spoke to each nation in its own language and dialect: Suppose, that the words delivered not only contain a just sense and meaning, but convey some instruction altogether worthy of a benevolent Being, superior to mankind: Could you possibly hesitate a moment concerning the cause of this voice? And must you not instantly ascribe it to some design or purpose? Yet I cannot see but all the same objections (if they merit that appellation) which lie against the system of theism, may also be produced against this inference. Might you not say, that all conclusions concerning fact were founded on experience: That when we hear an articulate voice in the dark, and thence infer a man, it is only the resemblance of the effects, which leads us to conclude that there is a like resemblance in the cause: But that this extraordinary voice, by its loudness, extent, and flexibility to all languages, bears so little analogy to any human voice, that we have no reason to suppose any analogy in their causes: And consequently, that a rational, wise, coherent speech proceeded, you knew not whence, from some accidental whistling of the winds, not from any divine reason or intelligence? You see clearly your objections in these cavils; and I hope too, you see clearly, that they cannot possibly have more force in the one case than in the other. (D. 117-118). 

Features of the Articulate Voice particularly worth noting are: 1) that what is heard from the clouds is regarded as a voice; 2) that what this voice is saying is intelligible to all who hear it; 3) that what is said is meaningful and instructive to all who hear it. These three features, Cleanthes urges, would make us instantaneously and unhesitatingly ascribe to it an intelligent cause of design that is similar to human intelligence. It is important to realize that in developing the Articulate Voice illustration, Cleanthes does not have recourse to analogical reasoning in his attempt to win over Philo. In fact, in his second paragraph above, he appears to be suggesting that the Voice example would be judged defective by the rules for assessing analogical arguments, given the dissimilarities between what is heard from the clouds and ordinary human voices. He speaks of the fact that, upon hearing this voice, ‘we could not possibly hesitate a moment concerning the cause of this voice’; that we must ‘instantly ascribe it to some design or purpose’. Cleanthes maintains that the disanalogies between the voice heard from the clouds and ordinary human voices make no difference to the inference to an intelligent cause for the articulate voice. He insists that it is the purposive design manifested in the activities of the articulate voice from the clouds - its loudness, extent, and flexibility to all languages; the rational, wise, coherent speech - which lead to an immediate inference of an intelligent cause. In short, belief in purposive design requires belief in a rational purposer. In one passage, Cleanthes elaborates on this type of non-analogical inference in Part 3, and emphasizes that irregular arguments leading to the conclusion of an intelligent cause of design are all based on purposiveness in design:  

Some beauties in writing we may meet with, which seem contrary to rules, and which gain the affections, and animate the imagination, in opposition to all the precepts of criticism and to the authority of the established masters of art. And if the argument for theism be, as you pretend, contradictory to the principles of logic; its universal, its irresistible influence proves clearly, that there may be arguments of a like irregular nature. Whatever cavils may be urged; an orderly world, as well as a coherent, articulate speech, will still be received as an incontestable proof of design and intention. (D. 119) 

In this passage, Cleanthes refers to such arguments as ‘irregular’, which contrast with what we can call ‘regular’ analogical arguments. Their irregularity stems from the fact that they do not utilize perceived resemblances between or among objects, and, in fact, do not involve the principle ‘like effects prove like causes’ which is at the foundation of analogical arguments. These inferences are immediate, namely, from the data to the conclusion: from purposive design to an intelligent cause of design. In another passage, he refers to such arguments as ‘natural’. They are natural because “they adhere to common sense and the plain instincts of nature”, and we must give our assent to them, because the reasons for assenting are so forceful that we “cannot, without the greatest violence, prevent it”.  

Cleanthes does not confine natural or irregular arguments to imaginary examples or instances: he maintains that the arguments for natural religion are all of this kind: 

Now the arguments for natural religion are plainly of this kind; nothing but the most perverse, obstinate metaphysics can reject them. Consider, anatomize the eye: survey its structure and contrivance; and tell me, from your own feeling, if the idea of a contriver does not immediately flow in upon you with a force like that of a sensation. The most obvious conclusion surely is in favour of design; and it requires time, reflection and study to summon up those frivolous, though abstruse objections, which can support infidelity. Who can behold the male and female of each species, the correspondence of their parts and instincts, their passions and whole course of life before and after generation, but must be sensible, that the propagation of the species is intended by nature? Millions and millions of such instances present themselves through every part of the universe; and no language can convey a more intelligible, irresistible meaning, than the curious adjustment of final causes. To what degree, therefore, of blind dogmatism must one have attained, to reject such natural and such convincing arguments? (D. 119)  

The analysis that I have presented here of the Articulate Voice illustration reveals that Cleanthes offers nothing to assist Philo to accept the analogical Argument from Design. In fact, he suggests that, given the vast differences between the voice heard from the clouds and human voices, it can be argued that the principle ‘like effects prove like causes’ cannot be utilized here. In the Articulate Voice illustration, it is the ‘irregular’ or ‘natural’ argument which, for Cleanthes, is the most convincing approach to the inference to an intelligent designer: he insists that wherever we observe purposive design, we are immediately led to believe that the design has been caused by intelligence. And, he emphasizes, purposive design is present throughout the universe:  

Millions and millions of such instances present themselves through every part of the universe; and no language can convey a more intelligible, irresistible meaning, than the curious adjustment of final causes. To what degree, therefore, of blind dogmatism must one have attained, to reject such natural and such convincing arguments? (D. 119)  

By insisting that the conclusion of an intelligent cause for the Voice heard from the clouds is reached through the natural or irregular argument and not through analogical reasoning, Cleanthes is attempting to instruct Philo that such irregular arguments are appropriate in these cases: the observation of purposive design leads immediately and irresistibly to the belief in an intelligent purposer for that design. 

Vegetable Library Illustration 

I turn now to Cleanthes’ Vegetable Library illustration:  

Suppose, that there is a natural, universal, invariable, language, common to every individual of human race; and that books are natural productions, which perpetuate themselves in the same manner with animals and vegetables, by descent and propagation…Suppose, therefore, that you enter into your library, thus peopled by natural volumes, containing the most refined reason and most exquisite beauty: Could you possibly open one of them, and doubt, that its original cause bore the strongest analogy to mind and intelligence? When it reasons and discourses; when it expostulates, argues, and enforces its views and topics: when it applies sometimes to the pure intellect, sometimes to the affections; when it collects, disposes, and adorns every consideration suited to the subject: Could you persist in asserting, that all this, at the bottom, had really no meaning, and that the first formation of this volume in the loins of its original parent proceeded not from thought and design? Your obstinacy, I know, reaches not that degree of firmness: Even your skeptical play and wantonness would be abashed at so glaring an absurdity. (D. 118) 

Unlike the Articulate Voice illustration which involves one type of cause (intelligence), the organic volumes involve two types of causes. Their immediate causes, descent and propagation, can account for how the vegetable volumes come into existence. Cleanthes insists that upon opening any of these volumes and witnessing their rational activities - “when it reasons and discourses; when it expostulates, argues, and enforces its views and topics: when it applies sometimes to the pure intellect, sometimes to the affections; when it collects, disposes, and adorns every consideration suited to the subject” - we could not doubt that the original cause bears the strongest analogy to mind and intelligence, despite having never observed the rational activities of the organic volumes constantly conjoined with an intelligent original cause. Therefore, a distinction is drawn between how the volumes come into existence (through immediate causes: descent and propagation), and the purposive activities they reveal through an intelligent original cause. The immediate causes of the natural volumes would presumably be observable, in the same manner that the immediate causes of animals and vegetables that we encounter in our experience are observable. But the intelligent original cause of the organic volumes is never observable by us, and yet, Cleanthes insists, in light of the rational purposive activities of the organic volumes, we would immediately conclude that they are caused by an intelligent original cause. 

In the case of the Voice illustration, Cleanthes insists that, from the perspective of the natural or irregular argument, the dissimilarities between the Voice speaking from the clouds and ordinary human voices are of no consequence, inasmuch as these natural or irregular arguments do not utilize the principle ‘like effects prove like causes’, and are not based on analogical reasoning. Regarding the Vegetable volumes, Cleanthes urges that we accept the conclusion of an intelligent original cause for the volumes, given our belief in the purposive nature of what we are hearing, and despite not having observed the intelligent original cause constantly conjoined with these organic volumes. And, bringing this illustration back to his efforts in Part 2, Cleanthes insists that we are not required to have actually observed an intelligent original cause designing worlds which are similar to the design of our world: all we need to observe is the purposiveness present in the design of natural objects and in the design of the world as a whole. Putting Cleanthes’ position generally, he is arguing in the case of both illustrations in Part 3 that the rules governing analogical arguments - especially the need for the strict application of the principle ‘like effects prove like causes’ - do not apply to natural or irregular arguments: we have never observed an intelligent cause of the Articulate Voice or an intelligent original cause for the Vegetable Volumes; and yet, he insists, that we would make an immediate inference to an intelligent cause of order for the Articulate Voice and the Organic Volumes.  

The inferences to an intelligent cause of the Articulate Voice and to an intelligent original cause of the Vegetable Library do not originate in reason, but in instinct. In Part 3, the force of the two illustrations is to convince Philo to acknowledge a first intelligent cause for the world, in the same manner as we would recognize a first intelligent cause for the Articulate Voice speaking from the clouds, and for the Living Vegetable Library, given that purposive design is observable in each of them. Cleanthes is making the point that, to the extent that Philo does not agree with the natural or irregular argument approach to an intelligent cause for the design of the world, this is due to Philo’s prejudice against approaches to God. 

At the conclusion of Cleanthes’ presentation of the two illustrative analogies, Pamphilus points out that “Philo was a little embarrassed and confounded” (D. 120). We can now understand why Pamphilus reports that Philo reacts as he does to Cleanthes. In Part 2, Cleanthes argued analogically to an intelligent cause for the design of the world; but in Part 3, he has recourse to irregular/ natural arguments - immediate inferences from rational purposive design to an intelligent original purposer/ cause. The latter inferences are not conclusions of analogical arguments, and, therefore, do not follow the rules for analogical reasoning. Accordingly, we must conclude that the illustrative analogies presented by Cleanthes in Part 3 cannot assist in moving Philo to accept the analogical Argument from Design presented by Cleanthes in Part 2. Further, two of Philo’s objections in Part 2, which Cleanthes highlights in Part 3 - that the dissimilarities between the voice heard from the clouds and ordinary human voices do not affect the inference to an intelligent cause for the voice heard from the clouds; and that the fact that we have not observed an intelligent original cause constantly conjoined with the vegetable volumes does not weaken the inference to an intelligent original cause - can now be understood to have no impact on the natural or irregular arguments which are not based on noted resemblances, except for purposive design; and do not require the observation of objects constantly conjoined. At this point, Philo is left wondering how the illustrations Cleanthes presents in Part 3 can assist in convincing him of the analogical Argument from Design presented in Part 2. Hence, Philo is justifiably embarrassed and confounded.  

Stanley Tweyman, University Professor 

York University 

Toronto, Ontario, Canada