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Thursday, June 25, 2020

Perceiving design

Alvin Plantinga, Where the Conflict Really Lies:

Perceiving Design?

In this chapter and the last we have been thinking about fine-tuning arguments for design, and Behe's biological arguments for design. We have been calling them, naturally enough, "arguments." But perhaps there is a better way to think about what is going on here. You are hiking up Ptarmigan Ridge towards Mt. Baker in the North Cascades; your partner points out a mountain goat on a crag about two hundred yards distant. She thus gets you to form a belief—that there is a mountain goat there. But of course she doesn't do so by giving you an argument (you are appeared to in such and such a way; most of the time when someone S is appeared to that way there is a mountain goat about two hundred yards distant in the direction S is looking). Perhaps what is going on in the arguments like Behe's, as well as the fine-tuning arguments of the last chapter, can be better thought of as like what is going on in this sort of case, where it is perception (or something like it) rather than argument that is involved.20

Fine-tuning and Behe-type arguments are ordinarily thought of as contemporary versions of a venerable theistic argument, the so-called "argument from design" (although a better name would be "argument for design" or to design). Design arguments go back to the "fifth way" of Thomas Aquinas and can also be found in the ancient world.21 A particularly well known (and often cited) version is due to William Paley (1743–1805):

In crossing a heath, suppose I pitched my foot against a stone, and were asked how the stone came to be there, I might possibly answer, that, for anything I knew to the contrary, it had lain there for ever; nor would it perhaps be very easy to show the absurdity of this answer. But suppose I had found a watch upon the ground, and it should be inquired how the watch happened to be in that place, I should hardly think of the answer which I had before given, that, for any thing I knew the watch might have always been there. Yet why should not this answer serve for the watch as well as for the stone? Why is it not as admissible in the second case as in the first? For this reason, and for no other, namely, that, when we come to inspect the watch, we perceive (what we could not discover in the stone) that its several parts are framed and put together for a purpose.22

Paley goes on to describe in more detail what we perceive, citing the intricacy of the design of the parts, the precision with which the various parts fit together to accomplish their function, the dependence of each part on others, and the like. He then claims that the same holds with respect to various features of the organic world: here too, he proposes, we can perceive design.

Every indication of contrivance, every manifestation of design, which existed in the watch, exists in the works of nature; with the difference, on the side of nature, of being greater and more, and that in a degree which exceeds all computation. I mean that the contrivances of nature surpass the contrivances of art, in the complexity, subtlety, and curiosity of the mechanism; and still more, if possible, do they go beyond them in number and variety; yet, in a multitude of cases, are not less evidently mechanical, not less evidently contrivances, not less evidently accommodated to their end, or suited to their office, than are the most perfect productions of human ingenuity.23

Paley devotes special attention to the eye, which he compares in detail to a telescope.

Now there are several ways in which this argument can be taken. Hume, for example, in his famous criticism of the argument in his Dialogues Concerning Natural Religion, sometimes seems to take it as an argument from analogy: the "contrivances of nature" resemble the contrivances of human beings; the latter are designed; therefore probably the former are too. At other times Hume seems to construe it as a straightforward inductive argument: all the things that exhibit "that curious adaptation of means to ends" which are such that we have been able to determine whether they are the product of design, are the product of design: therefore probably all things that exhibit that feature are the product of design; the contrivances of nature exhibit that feature; therefore probably they are the product of design.24 It can also be formulated as a so-called inference to the best explanation; roughly speaking, the argument taken this way claims that design, perhaps divine design, is the best explanation for various features—in particular biological systems—of the natural world. Paul Draper understands it this way, and states it as follows:

1. Some natural systems (e.g., the human eye) are mechanically ordered (i.e., they exhibit the same sort of order as watches and other machines produced by human beings).

2. Intelligent design is a very good explanation of mechanical order.

3. No other explanation (or no equally good explanation) of mechanical order is available.

4. Every instance of mechanical order has an explanation.

So,

5. Some natural systems were (probably) designed.25

There are still other ways of putting the argument. In the last chapter we saw that fine-tuning arguments can be stated in Bayesian fashion, as employing antecedent probabilities, but also as likelihood arguments, which eschew antecedent probabilities; Paley's argument too can be stated these two ways.

[...]

As Thomas Reid puts it,

No man thinks of asking himself what reason he has to believe that his neighbour is a living creature. He would be not a little surprised if another person should ask him so absurd a question; and perhaps could not give any reason which would not equally prove a watch or a puppet to be a living creature.

But, though you should satisfy him of the weakness of the reasons he gives for his belief, you cannot make him in the least doubtful. This belief stands upon another foundation than that of reasoning; and therefore, whether a man can give good reasons for it or not, it is not in his power to shake it off.27

Surely Reid is right? We don't in fact come to hold these beliefs by way of argument. I look at Paul and say to myself "Oh, oh, he's furious again—what have I done this time?" thus forming the belief that he is furious again. Do I form this belief by way of a quick but tacit induction, or an application of an analogical argument from premises involving the proposition that he looks a certain way, and when I look that way I am ordinarily furious? Clearly not. First, it seems that I don't ordinarily form any belief (any explicit belief, anyway) at all as to how Paul is looking: I move directly to the view that he is furious. Perhaps I could form such a belief: but typically I don't. I don't form a belief about how Paul looks and sounds ("his brow is knit; his eyes are narrowed to slits; his mouth is wide open; loud noises of such and such timber and pitch emanate therefrom"). And even if I did form such a belief, it would be far too crude to play the role of a premise in a decent analogical argument: any such description would fail to distinguish the way he looks from a thousand other ways which do not warrant the belief that he is furious.

Further, I sometimes ascribe to others emotions I have seldom if ever experienced myself; I could hardly do this on the basis of simple analogical reasoning from correlations between behavior and mental states in my own case. Moreover, much of the relevant behavior is such that I can't observe it in my own case: facial expression, for example, is extremely important, and I typically can't observe what sort of facial expressions I am presenting to the world. Of course we have mirrors; but our ancestors, prior to the advent of mirrors, no doubt sometimes knew that someone else was angry or in pain.28 And we ourselves form these beliefs without adverting to mirrors; how many of us carry a mirror, or (when in the grip of strong emotion) remember to consult it in order to establish correlations between mental states and facial expressions?

No doubt we come to beliefs about the mental states of others on the basis, somehow, of perception of their behavior: but not by way of an analogical or inductive inference from what we have observed about the connection between those bodily states and those mental states in our own case; if we did, our beliefs would not be well-founded and would certainly not constitute knowledge.29 Small children apparently form beliefs about the mental states of their parents long before they come to the age at which they make inductive inferences. The capacity for this sort of belief formation is not something one gains by inductive learning; it is instead part of our native and original cognitive equipment.30 We might put it by saying that we form beliefs of this sort in the basic way, not on the evidential basis of other beliefs, other propositions we believe. That is to say, we don't form these beliefs on the basis of inference. It is rather that we are hard-wired, as they say, to form these beliefs in certain experiential circumstances.

This account of belief formation is not, of course, restricted to beliefs about other minds. The same goes for beliefs about the past. I remember what I had for breakfast: Irish oatmeal; and of course I take it that my having breakfast was in the past. I don't form this belief—that it was in the past that I had breakfast—on the basis of any arguments: I simply remember it, which automatically involves the idea of the past, and automatically refers the event in question to the past. Indeed, it is exceedingly hard to see how I could acquire the thought that there are past events by way of an argument. What would be the premises? The same goes for perception: I look out the window and form the belief that the trees in my backyard are turning green. I don't ordinarily form this belief on the basis of an inference (the trees look as if they are turning green; usually, when things look that way they are turning green; therefore...). Instead, I form this belief in the basic way; I have been forming perceptual beliefs in this way ever since I was a small child, and the same, I daresay, goes for you.

How we form these beliefs is important along several different dimensions, but it is particularly relevant to the question how much warrant, or justification, or positive epistemic status the beliefs in question have. Based on a tenuous analogical inference or a speculative explanatory conjecture, these beliefs wouldn't have anything like the degree of warrant or positive epistemic status they actually do have; this basis wouldn't warrant anything like the degree of confidence we actually invest in them. They would then be more like risky conjectures or guesses than beliefs that are solidly grounded and can indeed constitute knowledge. On the other hand, if they are formed in the basic way, then they might very well constitute knowledge. For suppose (as seems to me to be true) that a belief B has warrant, that property or quantity enough of which is what distinguishes mere true belief from knowledge, just if B is formed by cognitive faculties functioning properly in the sort of environment for which we were designed (by God or evolution) according to a design plan successfully aimed at the production of true beliefs.31 Then if these beliefs about external objects, or the past, or the mental states of others are formed in the basic way, they could certainly constitute knowledge. And this is so even if there aren't any very good arguments for them. This sort of belief formation is not a result of movement from one set of beliefs (premises) to another (conclusion), but from a set of circumstances (being appeared to a certain way, for example) to a belief.

Now suppose we return to Paley's so-called design argument. Hume takes such arguments to be inductive or analogical; Draper takes Paley's version to be an argument to the best explanation. But there is a quite different way of interpreting it: this so-called design inference isn't a matter of inference or argument at all. I encounter something that looks designed and form the belief that it is designed: perhaps this isn't a matter of argument at all (anymore than in the case of perception or other minds). In many cases, so the thought goes, the belief that something or other is a product of design is not formed by way of inference, but in the basic way; what goes on here is to be understood as more like perception than like inference.32

...What I mean to stress, here, is that there are these two possibilities: there are non-argumentative design discourses as well as design arguments. Note further that the recognition of non-argumentative design discourses fits in well with the way in which we typically form beliefs about other minds. Indeed, insofar as design entails mental states on the part of some other person (the designer), the belief that a given object has been designed is a mental state-ascribing belief. If our other beliefs about minds, the mental states of others, are formed in that basic way, it is not implausible to suppose that the same goes for this sort of belief. The idea would be, therefore, that when you are on that walk with Paley and encounter a watch, you don't make an inference to the thought that this object is designed; instead, upon examining the object, you form the belief in that immediate or basic way. The same goes if you are on a voyage of space exploration, land on some planet which has an earth-like atmosphere, but about which nothing or next to nothing is known, and come across an object that looks more or less like a 1929 Model T Ford. You would certainly see this object as designed; you would not engage in probabilistic arguments about how likely it is that there should be an object like that that was not designed. You might also encounter something that was obviously designed, but such that you had no idea what its function was; you don't have to know what the function is in order to perceive that it has been designed by a conscious, intelligent agent.

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