Questions Does God exist?The watch and the eye

Does God exist?TheismTeleological (design)

The watch and the eye

The watchmaker argument

William Paley 1743 · 1805A watch found on the ground implies a watchmaker; the eye and living things imply a Creator.

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What it claims

Living things have an intelligent designer. Paley goes further: "Design must have had a designer. That designer must have been a person. That person is GOD."

Why

A watch whose parts are fitted to a purpose has a maker; living things show an arrangement at least as fine, so they have a designer.

The same idea through history

Cicero45 BCIn On the Nature of the Gods (II, 34-38), the Stoic Balbus already says: if Posidonius' mechanical sphere, which reproduces the motions of the stars, were brought to distant peoples, no one would doubt that it was the work of reason. Before a machine, a sphere or a clock, we do not doubt the intelligence that made it; why doubt it before the heavens?

Thomas Aquinas1270Fifth way (Summa theologiae I, q. 2, a. 3): things without intelligence still act for an end; so an intelligence must direct them, "as the arrow is directed by the archer".

Voltaire1766"Every work demonstrates a workman": Voltaire already compares the world to a clock, but stops at a maker of whom he knows almost nothing.David Hume1779In the Dialogues, Cleanthes defends the argument (the world is "one great machine"), then Philo criticises it. Paley writes twenty-three years later, taking these criticisms into account without naming Hume.

William Paley1802Paley gives the argument its most famous form: the watch found on the heath, then the eye compared with a telescope, and hundreds of examples taken from anatomy.

Robin Collins2009After Darwin, defenders of design move from living things to the laws of physics: this is the fine-tuning argument.Isaac Newton1713The order of the solar system can only come from an intelligent and powerful Being, Newton writes in the General Scholium added to the second edition of the Principia.

In short

"The watch and the eye" is an argument by William Paley (Natural Theology, ch. I to III (1802), 1802) on the question "Does God exist?" (answer: theism). Its claim: Living things have an intelligent designer. Paley goes further: "Design must have had a designer. That designer must have been a person. That person is GOD.". According to AskPhilosophy's logic check (Z3 solver), the argument is valid only if one grants a premise the author leaves unstated (P4). AskPhilosophy presents 4 objections, 4 of them with a documented reply, and the original text behind each premise, checked word for word.

Natural Theology, ch. I to III (1802)

Valid with an implicit premise

Walking across a heath, I strike my foot against a stone: it may have lain there for ever. But if I find a watch, I will never say that. Why? Because its parts are fitted to one another for a purpose: telling the time. So someone made it. William Paley, an English clergyman, applies this reasoning to living things. The eye is built like a telescope, and better: so it too has a designer. His book, Natural Theology (1802), was the textbook of a whole generation; the young Darwin admired it. It was also the main target of the theory of evolution.

click a premise to reject it

If you accept every premise, logic forces you to accept the conclusion. So the debate is about the premises.

Checked by a logic solver: the premises cannot all be true while the conclusion is false.
Without the implicit premise: Without P4, the computer finds a case where the eye shows contrivance, where chance, laws and the series of machines all fail, and yet another blind cause produces the contrivance: then there is no designer. This is the place natural selection will take.

Valid with P4. P1, P2 and P3 are not enough: one must also say that the blind causes ruled out are the only possible ones. Paley assumes this without proving it. Yet in chapter V he does examine another idea: a sorting that kept the viable forms out of a host of failed ones. He rejects it, because he sees no trace of such a process in nature. This is exactly the point where Darwin, in 1859, brings something new. Finally, the last sentence ("that person is God") goes beyond what the argument shows: at best it shows a designer, and Paley devotes other chapters to God's unity and goodness.

Analogy. You find a phone in the grass. You do not wonder whether the rain assembled it: someone designed it, even if you know neither the factory nor the engineer. Paley says: an eye is more ingenious than a phone. The whole question is whether, for living things, there is another way of making ingenious things.

Objections

Each objection is a conversation: click to see who replies and where the debate stands.

Hume (Philo, in the Dialogues) 1779 · attacks premise 1

We conclude that a house or a watch has a maker because we have seen thousands of houses and watches being made. But no one has ever seen a world or a living being being formed. Judging their cause by resemblance with our machines is reasoning without experience.

Paley replies

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William Paley 1802 · Paley's answer (he does not name Hume)

It would not weaken the conclusion even if we had never seen a watch made, nor known an artist capable of making one. Our ignorance of how it was made raises our admiration for the unknown artist; it does not make us doubt that he exists. And it does not matter whether that artist is a human or a being of another nature.

The debate goes on (our summary) Hume's heirs find the answer incomplete: before an unknown watch, we at least know that watchmakers exist and what they make; before life, we are precisely assuming a maker of another kind, whom no one has ever observed. Yet Paley shifted the debate skilfully: he no longer compares the whole universe to a house, as Hume's Cleanthes did, but one specific organ, the eye, to one specific instrument, the telescope, where the resemblance is strongest.

Where the debate stands (our summary)Paley argues that never having seen the object made takes nothing from the inference; Hume's heirs ask what guarantees the analogy when the supposed cause is of another kind. The debate continues in probabilistic form (see Hume's argument and the fine-tuning argument).

Charles Darwin 1859 · attacks premise 4

There is another blind cause: natural selection. Living things vary slightly in every generation; useful variations are kept, the others eliminated; over millions of years, small improvements add up and produce organs that seem designed. Darwin, who had admired Paley, later writes: "The old argument from design in Nature, as given by Paley, which formerly seemed to me so conclusive, fails, now that the law of natural selection has been discovered."

Paley replies

William Paley 1802 · Paley's answer in advance, to a related idea: a sorting of failed forms

Paley knew the idea of a sorting: nature might have produced countless forms, and only those able to live would have remained. He answers that it rests on nothing we observe: no such experiments are going on before our eyes, no force keeps pushing new forms into existence. And a random sorting would not explain the order of living things, arranged into genera and species.

Charles Darwin 1859 · What Darwin changes

Darwin does not speak of a single sorting among forms drawn at random, but of very small variations, observable in domestic animals, accumulated step by step. He grants that forming the eye in this way "seems absurd in the highest possible degree". But reason says it is possible if one finds many intermediate eyes, from the simplest to the most perfect, each useful to its possessor. And the order of genera and species is explained, in his view, by common descent.

See the rest of the debate (2)

Michael Behe 1996 · A modern defender of design

Darwin himself set the test: if a complex organ could not be formed by numerous small successive modifications, his theory would break down. Now the cell contains "irreducibly complex" systems: several well-matched parts, each of them necessary. Remove one, and the system stops working. Such a system cannot be built step by step, since the intermediate stages are useless. For Behe, this is Paley's watch found again at the level of molecules.

Kenneth Miller 1999

Summary: Miller argues that the parts of a supposedly irreducible system may first have served another function and then been recruited for the present one. The system need not form all at once: its intermediate stages may have been useful for something else.

The debate goes on (our summary) Paley's answer was aimed at the old idea of a one-off sorting (Lucretius' or Diderot's), not at Darwin's slow selection; on this point history has proved Darwin right, and selection is now observed. Against Behe, Miller's answer is that of most biologists. The debate goes on over specific cases, such as the bacterial flagellum.

Where the debate stands (our summary)Evolution by natural selection explains the adaptation of living things; the disagreement concerns its reach. Behe argues that certain cell systems cannot form gradually, Miller and others answer with the recruitment of parts. The debate over specific cases (for example the bacterial flagellum) continues.

Richard Dawkins (The Blind Watchmaker) 1986 · attacks premise 2

Paley is right on one point: the eye really does look designed, and it must be explained. But the analogy between telescope and eye, between watch and living organism, is false. The only watchmaker in nature is the blind forces of physics, deployed in a very special way: cumulative selection, which is neither chance nor design. It is a blind watchmaker.

Paley replies

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Richard Swinburne 2004

Darwin did not destroy the argument, he moved it. Selection only produces animals and humans from matter of a certain kind, subject to laws of a certain kind. It remains to explain why the universe has precisely those laws and that matter, able to produce life. The order of the laws of nature needs an explanation too.

The debate goes on (our summary) The debate then changes ground: it is no longer about the eye but about the laws and constants of physics (see the fine-tuning argument, and Dawkins' rejoinder: "who designed the designer?"). Many theists today accept evolution and place design in the laws, not in each organ.

Where the debate stands (our summary)Both camps admit that the eye has the appearance of design. The basic disagreement is about what explains that appearance, and whether the laws that make selection possible themselves call for an explanation (see the fine-tuning argument).

Hume (Philo, in the Dialogues) 1779 · attacks the conclusion

Even granting a designer, nothing says that it is one, perfect or good. This world could be "the first rude essay of some infant deity", abandoned afterwards, or the work of several gods, or of a god since dead.

Paley replies

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William Paley 1802 · Paley's answer (chapter XXV, without naming Hume)

The proof of God's unity is the uniformity of plan in the universe: the same gravitation makes the stone fall and the moon go round, the same laws are found everywhere, and nowhere do we enter the province of a different creator.

The debate goes on (our summary) A uniform plan suggests one author, or authors working together; it does not say that this author is all-powerful or good. Paley devotes another chapter to God's goodness, which has to face suffering in nature: this is the starting point of Darwin's bad-design argument.

Where the debate stands (our summary)Paley answers on the unity of the designer (uniformity of plan); perfection and goodness remain debated, notably with suffering in nature (see Darwin's bad-design argument). Basic disagreement: how far the order of the world allows us to describe the designer.

What today's voices say

Defend it

Alex O'ConnorGrants it is plausible to see an intelligence behind the majesty of nature, and that God behind evolution is not necessarily a God-of-the-gaps argument.

John LennoxHe argues from the language-like structure of DNA: seeing your name written in the sand, you at once infer an intelligent source.

Cliffe KnechtleHe compares the information in DNA to a message written in sand, which demands an intelligent mind.

Mohammed HijabHe calls the design argument the most intuitive, but says that on its own it only establishes the intelligence and knowledge of God, not an all-powerful God.

Criticize it