William Paley

Natural Theology, or Evidences of the Existence and Attributes of the Deity Collected from the Appearance of Nature

"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 forever. Nor would it perhaps be very easy to show the absurdity of the 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 anything I knew, the watch might have always been there ... the watch must have had a maker: that there must have existed, at some time, and at some place or other, an artificer or artificers, who formed it for the purpose which we find it actually to answer; who comprehended its construction, and designed its use .... Every indication of contrivance, every manifestation of design, which existed in the watch, exists in the works of nature, of being greater or more, and that in a degree which exceeds all computation. ... yet in a multitude of cases, are not less evidently mechanical, not less evidently contrivances ... than are the most perfect productions of human ingenuity. " Ch 1

This famous "Watchmaker" passage held sway for the better part of a century as a major influence from "natural theology" toward belief in God. Then, since the middle of the 19th century with Darwin's "Origin of Species" and the rise of evolutionary thought , Paley's thoughts were strongly criticized. Many credit David Hume with "destroying" Paley's argument by his philosophical discourse about the invalidity of using the analogy between a man-made contrivance and the biology of life. Most people who comment on the issue agree that Hume had a point and that Paley's particular view of design in living systems was flawed. But with the growing awareness of the complexity of the cell and the complex specified information in living system, a new view of intelligent design has been developed and Paley's Watchmaker is again being seriously considered. Dawkins reacts to it in his Blind Watchmaker.

A neat quote from Fred Hoyle notes that Paley is still in the running.
"It is ironic that the scientific facts throw Darwin out, but leave William Paley, a figure of fun to the scientific world for more than a century, still in the tournament with a chance of being the ultimate winner... Indeed, such a theory is so obvious that one wonders why it is not widely accepted as being self-evident. The reasons are psychological rather than scientific."

Another passage from Paley is cited by Lennox on pg 40 of God and Stephen Hawking

". . less surprised to be informed that the watch in his hand was nothing more than the result of the laws of metallic nature. It is a perversion of language to assign any law as the efficient, operative cause of any thing. A law presupposes an agent; for it is only the mode, according to which an agent proceeds: it implies a power; for it is the order, according to which the power acts. Without this agent, without this power, which are both distinct from itself, the law does nothing; is nothing." Natural Theology, 1802, p. 7.

Alvin Plantinga discusses the perception of design on p236 of "Where the Conflict Really Lies". I think that is an important part of the dialog.

p339-341 of Denton, Evolution: A Theory in Crisis in reference to Paley provides an excellent review and response to Hume's supposed negation of Paley's Watchmaker.

p339-341 "According to Paley, we would never infer in the case of a machine, such as a watch, that its design was due to natural processes such as the wind and rain; rather we would be obliged to postulate a watchmaker. Living things are similar to machines, exhibiting the same sort of adaptive complexity and we must, therefore, infer by analogy that their design is also the result of intelligent activity."

"One of the principal weaknesses of this argument was raised by David Hume, who pointed out that organisms may be only superficially like machines but natural in essence. Only if an object is strikingly analogous to a machine in a very profound sense would the inference to design be valid. Hume's criticism is generally considered to have fatally weakened the basic analogical assumption upon which the inference to design is based, and it is certainly true that neither in the eighteenth century nor at any time during the past two centuries has three been sufficient evidence for believing that living organisms were like machines in any profound sense. "

"It is only possible to view an unknown object as an artifact if its design exploits well-understood technological principles and its creation can be precisely envisaged. For this reason, stone age man would have had great difficulty in recognizing the products of twentieth-century technology as machines and we our selves would probably experience the same bewilderment at the artifacts of a technological civilization far in advance of our own."

"It has only been over the past twenty years with the molecular biological revolution and with the advances in cybernetic and computer technology that Hume's criticism has been finally invalidated and the analogy between organisms and machines has at last become convincing. In opening up this extraordinary new world of living technology biochemists have become fellow travelers with science fiction writers, explorers in a world of ultimate technology, wondering incredulously as new miracles of atomic engineering are continually brought to light in the course of their strange adventure in to the microcosm of life. in every direction the biochemist gazes, as he journeys through this weird molecular labyrinth, he sees devices and appliances reminiscent of our own twentieth-century world of advanced technology. In the atomic fabric of life we have found a reflection of our own technology. We have seen a world as artificial as our own and as familiar as if we had held up a mirror to our own machines." "Paley was not only right in asserting the existence of an analogy between life and machines, but was also remarkably prophetic in guessing that the technological ingenuity realized in living systems is vastly in excess of anything yet accomplished by man."

"The almost irresistible force of the analogy has completely undermined the complacent assumption, prevalent in biological circles over most of the past century, that the design hypothesis can be excluded on the grounds that the notion is fundamentally a metaphysical a priori concept and therefore scientifically unsound. On the contrary, the inference to design is a purely a posteriori induction based on a ruthlessly consistent application of the logic of analogy. The conclusion may have religious implications, but it does not depend on religious presuppositions."

"If we are to assume that living things are machines for the purposes of description, research and analysis, and for the purposes of rational and objective debate, as argued by Michel Polyani and Monod among many others, there can be nothing logically inconsistent, as Paley would have argued, in extending the usefulness of the analogy to include an explanation for their origin."

"It is interesting to speculate how the theory of natural selection might have fared in t he nineteenth century had the analogy between the living and mechanical worlds been as apparent then as it is today. The depth of the machine-organism analogy would have more than satisfied William Paley, and would certainly have provided Darwin's antagonists with powerful ammunition with which to resist the idea of natural selection."

"Although the argument for design has been unfashionable in biology for the past century, the feeling that chance is an insufficient means of achieving complex adaptations has continually been expressed by a dissenting minority, and this dissent is undiminished today."