Where the Conflict Really Lies: Science, Religion, and Naturalism (35 page)

For science to be successful, therefore, there must be a match between our cognitive faculties and the world. How shall we understand this fit? First, it is important to see that it is by no means just automatic or inevitable that there is such a match (as I’ll argue in more detail in the next chapter). Our faculties are designed to enable us to know something about
this
world; if the world were very different, our faculties might not serve us this way at all. Visual perception of our kind, obviously enough, requires light, electromagnetic radiation of the right wavelength; in a world where everything is always obscured by thick darkness, our eyes would be of no use. Something similar, of course, goes for hearing and our other perceptual faculties. We might think that our evolutionary origin guarantees or strongly supports the thought that our basic cognitive faculties are reliable: if they
weren’t, how could we have survived and reproduced? But this is clearly an error, as I’ll argue in the next chapter. Natural selection is interested in adaptive behavior, behavior that conduces to survival and reproduction; it has no interest in our having true beliefs.

So what more can we say about this required fit or match between our cognitive faculties and the world we seek to learn about? I’ve just mentioned perception; clearly this is a most important source of belief about the world; and one condition of the success of science is that perception for the most part, and under ordinary and favorable conditions, produces in us beliefs that are in fact true. This isn’t inevitable. It is possible that perception should produce in us beliefs that are adaptive, or meet some other useful condition, whether or not they are true.

For science to be successful, the world must display a high degree of regularity and predictability. As we saw in
chapter 4
, intentional action requires the same thing: we couldn’t build a house if hammers unpredictably turned into eels, or nails into caterpillars; we couldn’t drive downtown if automobiles unexpectedly turned into tea pots or rosebushes. Intentional action requires a high degree of stability, predictability, and regularity. And of course the predictability in question has to be predictability
by us
. For intentional action to be possible, it must be the case that we, given our cognitive faculties, can often or usually predict what will happen next. No doubt there could be creatures with wholly different cognitive powers, creatures who could predict the course of events in ways we can’t; that might be nice for them, but science as practiced by us humans requires predictability given
our
cognitive faculties. Furthermore, science requires more than regularity: it also requires our implicitly
believing
or
assuming
that the world is regular in this way. As the philosopher Alfred North Whitehead put it, “There can be no living science unless there is a widespread instinctive conviction in the existence of an
Order of Things
. And, in particular, of an
Order of Nature
.”
⁷

It’s an essential part of theistic religion—at any rate Christian theistic religion—to think of God as providentially governing the world in such a way as to provide that kind of stability and regularity. Let me quote again the Heidelberg Catechism:

Providence is the almighty and ever present power of God by which he upholds, as with his hand, heaven and earth and all creatures, and so rules them that leaf and blade, rain and drought, fruitful and lean years, food and drink, health and sickness, prosperity and poverty—all things, in fact, come to us not by chance but from his fatherly hand.
⁸

Christian theism involves the idea that
God
governs the world; that what happens does not come about by chance, but by virtue of God’s providential governance. The idea is that the basic structure of the world is due to a creative intelligence: a person, who aimed and intended that the world manifest a certain character. The world was created in such a way that it displays order and regularity; it isn’t unpredictable, chancy or random. And of course this conviction is what enables and undergirds science. Whitehead, as we saw, points out that science requires an instinctive conviction that nature is ordered; he goes on to attribute this widespread instinctive conviction to “the medieval insistence on the rationality of God.”
⁹

What does this “rationality” of God consist in? What might the medievals have meant in saying that God is rational? When they
discussed this topic, the medievals put it in terms of the question whether, in God, it is
intellect
or
will
that is primary. They thought that if
intellect
is primary in God, then God’s actions will be predictable, orderly, conforming to a plan—a plan we can partially fathom. On the other hand, if it is
will
that is primary in God, then his actions would involve much more by way of caprice and arbitrary choice and much less predictability. If it is intellect that is prior in God, then his actions will be rational—rational in something like the way that we are rational; if it is will that is prior, then one can’t expect as much by way of rationality. Aquinas championed the primacy of intellect in God, while William of Ockham endorsed the priority of will. This, of course, is vastly oversimplified (as is nearly anything one can say about medieval philosophy) but it conveys an essential point. Ockham seemed to think that God’s will was essentially unconstrained by God’s intellect (or anything else); God is free to do whatever he wants, even something that is irrational in the sense of contrary to what his intellect perceives as good or right. Ockham insisted that while in fact God chose to redeem humanity by becoming a human being, he could just as properly have chosen to do so by becoming a stone, a tree, or an ass.
¹⁰
He also claimed that God could have commanded hatred instead of love, adultery instead of faithfulness, cruelty instead of kindness; and if he had, then those things would have been morally obligatory. Aquinas, on the other hand, taught that God’s commands stem from his very nature, so that it isn’t so much as possible that God should have commanded hate rather than love.

The rationality of God, as Aquinas thought, extends far beyond the realm of morality. God sets forth moral laws, to be sure, but he also sets forth or promulgates laws of nature, and he creates the world in such a way that it conforms to these laws. The tendency of Ockham’s
thought, on the other hand, is to emphasize the freedom (willfulness?) of God to such a degree that he becomes completely unpredictable; and to the extent that God is completely unpredictable, the same goes for his world. There is no guarantee that the world at some deep level is law governed, or lawful; there is no guarantee that God’s world is such that by rational, intellectual activity, we will be able to learn something about its deep structure. In fact there is no reason to think, on Ockham’s view, that it
has
a deep structure. What Whitehead points out here is that modern science required a sort of instinctive conviction that God is more like the way Aquinas thinks of him than the way Ockham does.
¹¹
And indeed, many of the early pioneers and heroes of modern western science, the scientists propelling the scientific revolution, clearly sided with Aquinas. Thus Samuel Clarke: “What men commonly call ‘the course of nature’… is nothing else but the will of God producing certain effects in a continued, regular, constant, and uniform manner.”
¹²

This constancy and predictability, this regularity, was often thought of in terms of
law
: God sets, prescribes laws for his creation, or creates
in such a way that what he creates is subject to, conforms to, laws he institutes. Thus William Ames in
The Marrow of Theology
: “… the establishment of law and order, which is to be observed perpetually in the thing to which ordaining power applies. The constancy of God shines forth in that he would have all creatures observe their order, not for days or years but to the end of the world.”
¹³
Robert Boyle, the founder of modern chemistry, adds that “God [is] the author of the universe, and the free establisher of the laws of motion.”
¹⁴
According to Roger Cotes, who wrote the Preface to the second edition of Isaac Newton’s great work
Principia Mathematica
,

Without all doubt this world, so diversified with that variety of forms and motions we find in it, could arise from nothing but the perfectly free will of God directing and presiding over all.

From this fountain it is that those laws, which we call the laws of Nature, have flowed.
¹⁵

Later (mid-nineteenth-century) William Whewell, an extremely influential philosopher, scientist and polymath, put it like this: “But with regard to the material world, we can at least go so far as this—we can perceive that events are brought about not by insulated interpositions of Divine power, exerted in each particular case, but by the establishment of general laws.”
¹⁶
Finally, Albert Einstein again: “Every one who is seriously engaged in the pursuit of science becomes
convinced that the laws of nature manifest the existence of a spirit vastly superior to that of men.”
¹⁷

It is worth noting the connection here between moral law and natural law, or laws of nature. Boyle again: “The nature of this or that body is but
the law of God prescribed to it
[and] to speak properly, a law [is] but
a notional rule of acting according to the declared will of a superior
.”
¹⁸
Moral laws are promulgated by God for free creatures, who have it within their power to obey or disobey. Moral laws, then, are not inevitably obeyed; free creatures are able to opt for disobedience as well as obedience. The laws of nature, on the other hand, are promulgated for the inanimate world of matter; physical objects don’t get to decide whether to obey, say, Newton’s law of gravity.
¹⁹
In each case, however, we have the setting forth or promulgation of divine rule for a certain domain of application. It is important to see that our notion of the laws of nature, crucial for contemporary science, has this origin in Christian theism.

One thought, therefore, is that science requires regularity and lawful behavior on the part of the world: without this science would be impossible. But science involves law in another way: according to a very common view, these laws are
available
to us; we can discover them; and part of the job of science is to describe them. Recall Whewll: “But with regard to the material world, we can at least go so far as this: we can perceive that events are brought about not by isolated interpositions of Divine power, exerted in each
particular case, but by the establishment of general laws.”
²⁰
E. O. Wilson relates that upon reading Ernst Mayr’s 1942
Systematics and the Origin of Species
, he was overwhelmed by “a belief in the unity of the sciences—a conviction, far deeper than a mere working proposition, that the world is orderly and can be explained by a small number of natural laws.”
²¹
Finally, Stephen Hawking: “the more we discover about the universe, the more we find that it is governed by rational laws.”
²²
On this conception, part of the job of science is to discover the laws of nature; but then of course science will be successful only if it is possible for us human beings to do that.
²³
Science will be successful only if these laws are not too complex, or deep, or otherwise beyond us. Again, this thought fits well with theistic religion and its doctrine of the image of God; God not only sets laws for the universe, but sets laws we can (at least approximately) grasp. This thought also traces back to the beginnings of modern science. According to Kepler,

Those laws are within the grasp of the human mind. God wanted us to recognize them by creating us after his own image so that we could share in his own thoughts… and if piety allow us to say so, our understanding is in this respect of the same kind as the divine, at least as far as we are able to grasp something of it in our mortal life.
²⁴

There is still another important way in which theism is hospitable to science: theism makes it much easier to understand what these laws are like. The main point here has to do with the alleged
necessity
of natural law. Note first that not just any true universal statement is a law.

(1) Everyone in my house is over 50 years old

is a true universal proposition; still, it’s not a law. Nor is the problem that this proposition contains a reference to a specific person (me) or specific physical object (my house).

(2) Every sphere made of gold is less than 1/2 mile in diameter

is a (presumably) true universal proposition, but is not a law, and the same goes, no doubt, for

(3) No provost of a large university climbs at the 5.12 level.

While these propositions are true and universal in form, they aren’t laws. Why not? One answer: because they are merely
accidentally
true. They are accidentally true universal generalizations; laws, however, are not accidentally true.

How shall we understand this non-accidentality? Those who endorse natural laws typically think of them as in some way
necessary
; there is a certain necessity about natural laws.
²⁵
However, it seems
that laws are not
logically
necessary; it seems logically possible that, for example, there be a pair of particles that do not attract each other with a force inversely proportional to the square of the distance between them, even if Newton’s inverse square law is indeed a natural law.
²⁶
It seems possible that God accelerate an object from a speed slower than
c
, the speed of light, to a speed greater than
c
. Still, that this doesn’t happen seems necessary in some way—
causally
necessary, as people say, or
nomologically
necessary. But what kind of necessity is that? Logical necessity we know and love: but what is this causal or nomological necessity?