When analyzing an unknown object, one of the first things to consider is: "Is this natural or artificial (intelligently designed)?" As a scientist/engineer it is difficult to imagine a design that has absolutely no purpose. Does purpose provide a clear distinction between intelligent design and evolution? If the purpose is completely unknown, is it possible to deduce design with confidence?

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    Of course it is. I’m going to splatter a tomato on the wall right now.
    – user62907
    Jul 10, 2023 at 18:05
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    @thinkingman But your splattered tomato has a practical purpose: serving as a counter-example to this question!
    – g s
    Jul 10, 2023 at 18:05
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    @gs As is common with many topics in philosophy, this would come down to semantics and what purpose means. Technically, everything we do has a reason. In fact, everything in the universe occurs for a reason. One may call that a purpose as well but it doesn’t seem to match with how most see the term purpose to mean. If I was bored today and splattered a tomato today, one may still argue that the practical purpose was to remove boredom.
    – user62907
    Jul 10, 2023 at 18:18
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    This answer is relevant: 'Is there a general theory of intelligence and design that would allow us to detect the presence of design in an object based solely on its properties?' philosophy.stackexchange.com/questions/99762/…
    – CriglCragl
    Jul 10, 2023 at 19:51
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    @StevanV.Saban It sounds like you have your question backwards. As stated, your question is about the presence of design implying purpose, but I get the sense you really want to ask about the presence of (observed) purpose implying design. Throw in some equivocation on "purpose" being "accomplishes a function" versus "deliberate intent of an intelligence", and you have a recipe for confusion.
    – R.M.
    Jul 11, 2023 at 16:23

6 Answers 6


With respect to another characteristic, a characteristic may be necessary, sufficient, neither, or both.

Necessity: the antecedent is true whenever the consequent is true, the antecedent is true (A if C). One can remember using the mnemonic: The Necessary antecedent has a Name whenever the consequent is called Socrates.

Sufficiency: whenever the antecedent is true, the consequent is true. (C if A). One can remember using the mnemonic: Whenever the Sufficient antecedent is called Socrates, the consequent has a Name.

Necessity and sufficiency is if and only if: the antecedent is only true when the consequent is true, and the consequent is only true when the antecedent is true. (A iff C).

Taking purpose as synonymous with intentionality, not practicality:

Purpose is necessary for design, as expressed in Pertti Ruismäki's and Davide Gudeman's answers.

Purpose is not sufficient for design, as anyone who has attempted to compose a work of art or argument and found it much more difficult than expected can attest.

Neither purpose nor design are sufficient for the appearance of design: "Without knowing that you splattered that tomato to make a point, how could I look at a given tomato splatter and deduce: Aha, you are making a point?"

Neither purpose nor design are necessary for the appearance of design, see e.g. crystal formation, which can create stones that appear to have been cut by a jeweler.


It depends on the context. If one takes design to mean happening by humans vs. chance, yes. If one takes design to mean happening as intended by humans, then no, since that requires purpose by definition.

For example, a human may cause rocks to scatter about in a particular configuration after driving in a car even though the configuration may look like it was scattered by other natural elements such as the wind. This would technically be an example of human “design” in that it was created by humans. An example of purposeful design is a watch.

  • i agree, but can think of a better example, maybe. purposefully throwing a rock at a tree and it accidentally - not on purpose - hitting a bird. the shot was aimed and on purpose, and its trajectory was by design. its end was not purposeful! what's missing from end = purpose is not design but intent, imvho. i designed a time machine but not for this purpose!
    – user66760
    Jul 11, 2023 at 1:53
  • You are correct about context and I like your answer and this leads to my follow up: If the product of evolution produces a behavior or visual change that scientists observe as having a purpose, then how can observations alone provide evidence for or against intelligent design?
    – user64314
    Jul 12, 2023 at 17:52
  • The problem with evolution being supposedly designed is that in order to design it, one needs a designer. But without direct observation of a mechanism of this design, and direct evidence of this designer creating evolutionary processes, one cannot conclude design. As long as evolution can be explained without design (which it has been), there is no need to postulate a designer. Even if a certain observation was very improbable under a blind process, it STILL wouldn’t count as evidence for design. Since it doesn’t increase the probability of the designer’s existence
    – user62907
    Jul 12, 2023 at 18:43

There is no accidentally on purpose

Can you dream up a design, design something by accident? Dreams need serve no purpose to you, let alone anyone else. My chemistry teacher at school told us that the double helix design of their Watson and Crick model for DNA was thought up in a dream.

According to Dr. Watson's alma mater, Indiana University, in his dream, he stumbled upon the double helix image for the DNA chain through his dream of a spiral staircase

I don't think creativity is always deliberate! Anyway, the unconscious is out of our conscious control, and not purposeful ('Freudian slip').

I think we can accidentally follow - not just create - a design too: it's not trivial that no-one means to defy God's plan (not saying there is any such thing), whether or not anyone can

I think you can drive a car somewhere, fix the mind on it, a planned intent to drive that you act on, but without a purpose.

What about sleepwalking?

  • anyway, depends what you mean "do or plan (something) with a specific purpose in mind" in this sense OFC it is impossible
    – user66760
    Jul 13, 2023 at 6:06

All design is made for a purpose by definition. Purposeless configurations are not designed, they are formed randomly.

If you don't know the purpose or the designer, you cannot say with confidence whether the object is designed or not. Some deeper analysis of the structure may reveal that the object is artificially manufactured and thus designed, but this is not always the case.

  • Do you believe this provides an important distinction between intelligent design and evolution?
    – user64314
    Jul 10, 2023 at 18:17
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    @StevanV.Saban If you have no purpose, no designer, no signs of artificial manufacturing, then you have no reason to even suspect that the object has been designed. In the context of intelligent design the object in question is the whole Universe minus the designer. Who designed the designer? If no-one, if he evolved naturally, then you have no reason to doubt the natural evolution of the Universe. The designer is a useless concept that doesn't answer any questions. Jul 10, 2023 at 19:24
  • If we consider the quote by Max Tegmark, "Intelligence is the ability to accomplish goals", and no goal is being accomplished by something, then it is not the result of intelligence.
    – Scott Rowe
    Jul 10, 2023 at 19:38
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    @StevanV.Saban: Did...you ask a leopard about that? Or was that merely the opinion of some humans? It's sounding like you want a form-follows-function setup, where "purpose" is any property of a construction which can be proven to implement some functionality.
    – Corbin
    Jul 11, 2023 at 15:42
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    @Corbin You are right. It's the opinion of some humans. I am looking for a way to distinguish the products of evolution from the products of intelligent design. Form follows function is a good engineering design principle that applies to human technology but does it apply to all intelligent design? If the product of evolution produces a behavior or visual change that scientists observe as having a purpose, then how can observations alone provide evidence for or against intelligent design?
    – user64314
    Jul 11, 2023 at 16:18

The concept of “purposeless design” involves a contradiction. You can, however, have purposiveness without a purpose; that is, you can have the appearance of design without design (see Kant’s Third Critique).

  • Is natural selection an example of a process that has the appearance of design without design?
    – user64314
    Aug 2, 2023 at 0:52
  • Natural selection is a mechanism that purports to generate the appearance of design, as an effect. Kant has something else in mind, viz. self-organizing entities. Aug 3, 2023 at 12:32

Design is always the product of deliberate mental activity. Anything that happens in the absence of mental activity is not by design, and if there is mental activity going on, but the outcome is not what was intended, then that is also not by design. So, for something to be designed implies that it was produced as a deliberate result of mental activity. Consequently, your question can be reduced to whether it is possible for mental activity to be deliberate but have no purpose.

Now you have to define purpose. People sometimes do things capriciously, meaning that they have no well-defined purpose in doing so. Does that mean there was no purpose at all? You can almost always apply some vague purpose to capricious activity: knocking your friends hat off: impulsive aggression? Tossing the last bit of bread from your sandwich into an ant pile: impulsive curiosity to watch the ants scramble? Constructing a Rube Goldberg device: simple delight in complexity?

Until you can answer whether it is possible to do something deliberately with no purpose whatsoever, you can't really answer this question. I'm inclined to think it is not possible because I can't think of any examples, but my inability to think of examples is not really an argument.

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    Leopard spots are a simple and fascinating counterexample, with connections to cellular automata and genetic algorithms.
    – Corbin
    Jul 11, 2023 at 4:30
  • @Corbin Counter examples to what? Jul 11, 2023 at 6:07
  • The design of leopard spots, as explained by Turing, was the result of natural selection. The "deliberate mental activity" that Turing and others undertook to understand the design is not the same as the process which originated the design. For what it's worth, I don't think this answer can be salvaged.
    – Corbin
    Jul 11, 2023 at 15:56
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    @Corbin, I can't see any connection between this comment and my answer. Are you thinking that leopard spots are a "design" in the sense discussed in the question? If so, you are misunderstanding the question. Jul 11, 2023 at 16:27

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