7C. Can design be scientific?  (medium-long version) 
    This section examines arguments -- practical, methodological, metaphysical, and trivial -- for an Open Science (that includes theories of design) and a Closed Science.  The basic question is simple: In scientific thinking and education, do we want to give a higher priority to logic or naturalism?

    PRACTICAL Questions
    Design theories can be scientifically useful by improving our search for truth, and by stimulating creativity and critical thinking.

    LOGIC and TRUTH
    Logic requires that, during any intellectually rigorous attempt to explain the origin of an observed feature, scientists should consider all possibilities, including both non-design and design.  When we ask, "Has the history of nature included only origins by non-design?", we should be open-minded in our search for truth, willing to accept either YES or NO as the answer.  Whether or not design was involved in the origin of a feature, an Open Science will allow, but cannot guarantee, reaching a correct conclusion.  But if design really did occur, a restrictive Closed Science (which ignores the possibility of design) will guarantee a false conclusion.  If scientists ignore a theory that might be true, this does not seem logical.
    To help us think about the question, "Is MN always the best way to do science?", Paul Nelson asks us to imagine two possible worlds:  one world has a history of nature with all events caused by only natural process, while the other world has a history of nature that includes both natural and non-natural events.  When we ask, "Which type of world do we actually live in?", we hope our science will help us, not hinder us, in our search for the answer.  But in one of the two possible worlds, a science that is restricted by MN must inevitably reach the wrong conclusion.  By contrast, in either world a non-MN science will allow (although it cannot guarantee) reaching the correct conclusion.

    STIMULATING IDEAS
    Critical thinking about non-design will encourage a more accurate evaluation of non-design theories.  And this critical thinking, which is allowed in Open Science but not in Closed Science, can stimulate creative theoretical and experimental research by advocates of both design and non-design.  For example, Mike Behe's questions about irreducible complexity have inspired advocates of neo-Darwinism to construct counter-arguments for defending, new experiments for supporting, and modifications for improving their theories.
    A common concern is that design will be a "science stopper" if the response to a challenging problem is that "there is no natural explanation so it's useless to search for it."  But the potential chilling effect is greatly exaggerated.  Most areas of science are not affected by design.  And many scientists will persevere after hearing a claim that "perhaps this feature wasn't produced by natural process," because they think a natural explanation exists and they want to find it.  { And advocates of design want non-design research to continue, because this will improve the quality of evaluation for nondesign and design, because they want to find the truth. }

    PAST AND PRESENT
    In the past, some claims for design have seemed foolish after science found a natural explanation.  Are all claims for design destined to fail?  Although past failures are a reason for caution, we can learn from history, and theories can improve.  A current design theory should be judged on its own merit, not the weakness of superficially similar theories in the past.  Evaluating each theory individually will help us avoid the extremes of assuming that a claim for design is always justified (whenever current science cannot explain a feature) or that a claim for design could never be justified, or that design has never occurred.
    Also, judgments can be reversed.  For example, the claims of Paley are now being reconsidered, but with increased knowledge, by Behe and others.  And for other questions, such as the origin of life, non-design has never offered an explanation that seemed satisfactory.

    STATUS QUO
    Currently, most scientists don't propose design theories.  Should we define science by the majority behavior of current scientists?  No, it doesn't seem wise to let "what is" determine "what should be" by assuming that current methods are necessarily the best of all possible methods, in every area and every situation.
    A common argument for the status quo is that "modern science is making wonderful progress, so we should not change it."  But this conclusion is not justified if, as we have good reasons to expect, a tolerance of design would have very little overall impact on practical productivity, and would not hinder the progress of science.

    METHODOLOGICAL Questions
    Typically, questions about methods are in four areas:  history, agency, observability, and falsification.
    HISTORY:  Theories of design are proposed in historical science (to study events in the past) but not in operations science (to study ongoing events in the present).  The logic is similar in both types of science, but there are differences.  For example, historical data cannot be repeated and "controlled" but this is possible with experiments in operations science.  And instead of making logical predictions, historical scientists make logical retroductions by asking, "What theory could explain the historical data we have observed?"  But these limitations occur in all historical sciences (astronomy, geology, archaeology, evolutionary biology,...) and they pose no special problems for design.
    AGENTS:  In contrast with situations where a mechanistic theory can provide an adequate description, sometimes "what happens" depends on the decisions and actions of an agent, which introduces an element of unpredictability.  This occurs in design theories and in other areas of science (such as psychology and sociology) that involve agent action, and in history.  When the methodology of agency is being analyzed, two important principles are:  1) a basic design theory claims only that "design-directed action did occur" but says nothing about the details;  2) in historical science we only have to explain what did occur, not predict what will occur.
    OBSERVABILITY:  Because an unobservable cause can produce an observable effect, an observable effect can let us scientifically infer the existence of an unobservable cause.  By using this important principle, scientists can logically propose electrons (in chemistry) and ideas (in psychology) even though electrons and ideas cannot be observed.  Why?  Because some observations are most satisfactorily explained if thoughts and electrons exist.  Similarly, if we observe "signs of design" we can logically infer the existence of design-directed action, even if the agent and action were not observed.  In historical science, supernatural agency and natural agency are methodologically similar, since -- if the results of agent-action can be observed -- it does not matter whether the action (or agent) could not have been observed or simply was not observed.
    FALSIFICATION:  It is impossible, using formal logic, to prove any scientific theory is true or false.  But for a scientist, falsification is a high degree of logically justified confidence in falsity, and a design theory is falsified when a non-design theory seems highly plausible.  Conversely, when production by non-design seems implausible and the evaluative status of non-design decreases, the status of design increases, due to a mutually exclusive relationship:  a feature was produced by either non-design or design.  Therefore, evidence against non-design is evidence for design, and testing for non-design is a way to test for design.  Since the status of design can be increased or decreased by empirical evidence (by observations), a theory of design is empirically responsive and is testable.  { When critics try to empirically refute a design theory, they are confirming its testability. }

    Do you think the design theory in Section 7A is a result of scientific thinking?  Consider the process:  You observe a signal, notice a pattern (with prime numbers), creatively construct and critically evaluate theories, and conclude that design-directed action is a more plausible explanation than undirected natural process.  This is logical scientific thinking.
    THE BOTTOM LINE:  When scientists evaluate a theory of design, they are using conventional scientific methods of inference, analogous to the methods used by detectives in forensic science.  If you think that, in some situations, a crime detective can logically conclude "this death occurred by murder," you should be satisfied with the methodological effectiveness of design inferences.  For most critics of design, the main concerns are metaphysical, not methodological.

    METAPHYSICAL Questions
    MIRACLES?  A basic design theory -- which claims that a feature was produced by either natural design and construction or supernatural design and creation -- does not require miracles, but it does allow miracles.  /   Since the logic of science assumes consistency and reproducible results, would a miracle mean the end of science?  No.  This methodological concern is unwarranted.  If, despite occasional miracles, the universe usually operates according to normal natural patterns*, science will be possible and useful.  { * A theist claims that the stability of nature, which allows scientific investigation, is due to the designing and sustaining of nature by God. }
    LIMITED CLAIMS:  An exploration of design in any area (in homicide, radioastronomy, origins,...) is a two-step process:  ask "Was there design-directed action?" and then investigate the details.  Much confusion about design is caused by ignoring the important distinction between these two stages, between what a theory of design does claim (that design occurred) and what it does not claim (that it can explain the details, the "how, when, why, and who" of the design-and-production process).  We should judge a design theory based on what it is, not what it isn't but never claimed to be.  /   Many methodological demands -- for example, expecting a design theory to provide detailed explanations and make precise predictions -- seem unreasonable when we try to achieve a match between the limited claims made by design and the methods used to justify these claims.
    SUPPLEMENTED THEORIES:  A basic design theory can be supplemented with details about the designer's identity and actions.  For example, a theory proposing design for the origin of increasingly complex life on earth could be supplemented with proposals for old-earth creation by God, young-earth creation by God, creation by another supernatural agent, or construction by natural extraterrestrial agents.  Each explanation (the design theory and the four supplemented theories) can be evaluated independently on its own merits, to generate five different estimates of scientific plausibility.
    DESIGN AND CREATION can be related, but are not the same.  When thinking about design and/or creation, two useful general principles are:  evaluate each theory based on what it claims, no more and no less;  compare theories carefully, to find their similarities and differences, and evaluate accordingly.  /   A basic design theory is limited to claims that can be scientifically evaluated.  For example, biochemical analysis might help us determine whether a particular system was produced by design or non-design, but it probably could not help us determine whether design-action was by God or space aliens.
    The major differences between design and creation are summarized in the table below, which is the table from Section 6B with two additions: a column for a theory of intelligent design (ID) about biological development, and a question asking, Does this theory claim that "God did it"?

The table above is explained more clearly in a new page about Logical Evaluations of Evolution and Creation.  More information about theories of design and creation (their claims, relationships,...) is in the FULL-LENGTH VERSION of Sections 7A-7G.

    TRIVIAL Questions
    NATURAL SCIENCE:  A claim that "in natural science, natural phenomena and natural history should be explained by natural causes" is trivial.  It is just faulty circular logic (assuming "science is natural" in order to conclude "science is natural") camouflaged with verbal ambiguity (using "natural" to mean both "pertaining to nature" and "normal appearing").  To avoid this sloppy logic, instead of "natural science" we should use terms that are more general (science) or more specific (physical science, earth science, biological science, social science,...).
    SCIENCE AS A GAME:  Another trivial argument is to claim that we should view science as an intellectual "game" played with a set of rules, established by tradition and by consensus of the scientific community, which include an exclusion of design.  But it seems more rational to view science as a real-life activity with goals, not an artificial game with rules.  {the important difference between reality and games is illustrated by a StrongMan Contest}

    METHODOLOGICAL NATURALISM is a proposal to restrict the freedom of scientists by requiring that scientific theories should postulate only natural causes.  The logical process leading to an acceptance of methodological naturalism (MN) can be trivial, if MN is just a slogan (borrowed from others) based on a small amount of shallow thinking.  Or MN can be a concise summary for a large amount of deep thinking about the goals and methods of science.
    When examined closely, some arguments for a Closed Science (restricted by MN, excluding design) seem rather trivial.  Other ideas, especially those encouraging us to think about practical effects and methodology, are more worthy, if only because they can stimulate productive thinking and discussion.  But none of the arguments for enforcing a rigid MN seem convincing, and the more deeply we think about an Open Science, the better it looks.
    Scientists who propose design always begins their thinking with MN, but they don't insist on ending with MN, since their range of acceptable conclusions is expanded.  They are using the process of science, with conventional methods of inference.
    By contrast, MN lets a scientist bypass the process of science and immediately conclude that "it happened by natural process."  Reaching a scientific conclusion without doing any science is certainly efficient, but is it effective in advancing our search for truth?  MN is fast, but is it wise?  Does a rigidly enforced MN help or hinder our efforts to develop an accurate understanding of nature?

    This section closes with a real-life example and some tough questions.  Consider a theory of design about the origin of life.  Is this theory scientific?  If not, what would make it unscientific:  a claim that a formation of life by undirected natural process is extremely improbable?  a perception that this claim implies a non-natural cause?  a proposal of a non-natural cause?  Is there any limit to the severity of criticism before a design theory becomes unscientific?  If similarly severe criticism is accompanied -- not by a proposal for design or creation, but for a new natural theory -- does this make it scientific?  Is it all right to admit "we are far from finding the answer," but not to say "maybe there is no natural answer"?  Is it necessary to confine and control the ideas of scientists by removing their freedom to think that "maybe..."?

    7C. Can a design theory be scientific?  (long version)
    ( the title has been changed to "Can design be scientific?" )
    Even though a claim for design can be supported by the methods of science, by a logical analysis of empirical observations, some people claim that a design theory is inherently non-scientific.  Why?  This section examines arguments for considering design theories to be nonscientific, along with counter-arguments.

    Why is design controversial?
    Imagine that, as in Contact (the novel and movie by Carl Sagan), scientists observe a signal containing a series of prime numbers, and they propose a design theory to explain the signal's origin.  Nobody would dispute the scientists' right to propose this theory, and there would be no controversy about whether or not their proposal is authentically scientific.
    In most ways, a design theory to explain prime numbers (or the stone faces on Mt Rushmore) is logically equivalent to a design theory to explain the first life.  In one way, however, there is an important difference, which explains why one theory is calmly tolerated while the other is a topic for intense debate.  From experience we know that human intelligence and technology can produce signals and sculptures, so for these features design-and-construction by humans (or by space aliens with adequate intelligence and technology, or...) seems plausible.  But if there was no intelligent life in nature to design and construct the first life, a theory of design seems to imply design-and-creation.  This is a cause for concern among some scientists and nonscientists, for reasons discussed in the rest of this section, even though design-and-construction theories are not controversial.

    What are the limits of science?
    When deciding how to define science and its methods, we can choose to restrict the freedom of scientists by requiring that scientific theories should postulate only natural causes.  This proposed limit is methodological naturalism (MN).  A second limit follows logically:  If MN is accepted, and if an event actually does involve a non-natural cause, then any scientific description of this event (in terms of only natural causes, as required by MN) is guaranteed to be incomplete or incorrect.  This logical conclusion is humility about methodological naturalism (MN-Humility).
    Each limit answers a question.  For MN the question is "What are the limits for what can claim to be science?", and the answer is a proposal.  For MN-Humility the question is "What are the limits for what a restrictive MN-science can claim to explain?", and the answer is a logical certainty.

    Should we accept methodological naturalism?
    In 1998, I was willing to support either of two options:  1) reject MN and include design in science, or  2) adopt MN but also adopt MN-Humility by explicitly acknowledging the limitations of MN-science.  Here is how I summarized the limits of what MN-science should be allowed to claim:
    "We can view a restricted MN-science as one aspect of a broader 'search for truth' that considers all possibilities without imposing metaphysically biased restrictions on theorizing.  In this open search for truth, what is the role of MN-science?  It can be a valuable resource that should be respected as an expert witness, but it should not be the judge and jury when we're defining reality and rationality." (Rusbult, 1998)
    The remainder of Section 7C explains why, two years later when I began to revise this overview, my views had changed.  Now I think that -- instead of accepting MN and then apologizing for its logical deficiencies -- we are behaving more rationally if we simply reject MN.  If we are serious about searching for truth, it seems wise to adopt an Open Science in which scientists always begin with MN, but do not insist that it is logical to always decide, before looking at the evidence, that we should end with MN.
    One reason for rejection is that -- in the scientific and educational communities, and in the public media -- there is a consistent disregard for MN-Humility.  Instead of explaining the logical limitations of MN-Science, there is a strong implication that the conclusions of Modern Science must be true because a non-scientific theory does not deserve serious consideration in a modern society.  This implication is widespread, despite the logical inconsistency of using MN to bypass the process of science and then claiming the authority of science as support for the unavoidable conclusion required by MN (that "according to science the history of nature was all natural") even if this conclusion would not be supported by the process of science, by a logical analysis of observations and a critical evaluation of all competitive explanations.
    But the main reason for my change is practical utility:  I've become more thoroughly convinced that, since design theories can be scientifically useful, science should include these theories instead of automatically rejecting them, as demanded by MN.

    Logical Methods and Design
    A defense of Closed Science often begins at a superficial level, with an assumption -- that "natural science" is natural -- which isn't questioned.  At this level, the only question being asked is whether design violates a tradition of methodological naturalism.
    But we can move to a deeper level by thinking about scientific utility, by asking "What would be the practical effects of an Open Science that includes design?" and "Does a rigidly enforced MN help or hinder our efforts to gain an accurate understanding of nature?"  Although some aspects of these questions have been discussed above, other important concerns about scientific utility -- concerns involving the logical methods used in science -- are examined in the remainder of this section.  I hope you'll find some useful ideas in the following discussion.

    Observable Effects
    When we're evaluating the methodology of design, an important principle of cause-and-effect is that an unobservable cause can produce an observable effect.  If we examine a feature and observe distinctive signs of design we can logically conclude that design has occurred, even if we have not directly observed the agent who formulated the design or performed the directed action that produced the designed feature.
    During the history of science, this principle -- that an observable effect can let us scientifically infer the existence and action of an unobservable cause -- has been debated, and its logical validity and scientific utility have been accepted by scientists and philosophers.  Larry Laudan (1977, 1984) describes a conflict between beliefs that resulted in a significant decision about the methodological foundations of science.  In the early 1700s, some interpreters of science claimed that Isaac Newton had constructed his theories only by inductive generalization from observations, and had refused to speculate about unobservable theoretical entities.  A claim that Newton's method of theorizing was based on a commitment to "no unobservable components in theories" is challenged by modern historians and philosophers, but for awhile this methodological strategy was influential in science and philosophy.  Scientists were inspired to mimic the methods they mistakenly thought Newton had used, so they tried to develop theories that -- consistent with the positivist models of knowledge being developed by philosophers -- did not include unobservable causal entities.  But by the 1750s it was becoming apparent that many successful theories, in a wide range of fields, in operations science and historical science, depended on the postulation of unobservable entities.  Thus, there was a conflict between positivist goals for science and the actual theories of science. 
    Instead of giving up their non-positivist theories, the scientists and philosophers "sought to legitimate the aim of understanding the visible world by means of postulating an invisible world whose behavior was causally responsible for what we do observe. ...  To make good on their proposed aims, they had to develop a new methodology of science,... the hypothetico-deductive method.  Such a method allowed for the legitimacy of hypotheses referring to theoretical entities, just so long as a broad range of correct observational claims could be derived from such hypotheses. (Laudan, 1984; p. 57)"
    Using this logical methodology, modern scientists often propose that observed effects were produced by an unobserved cause.  In hypothetico-deductive reasoning, the only requirement -- even if a cause cannot be directly observed -- is that effects can be observed.  This requirement is fulfilled by a theory of design which claims that a cause (the design-directed action involved in producing a feature) can be inferred if, when we examine a feature, we observe distinctive signs of design.  {more about positivism}

    Historical Science
    Theories of design are proposed in historical science (to study events in the past) but not in operations science (to study ongoing events in the present).

    In both types of science, the logic is similar.
    Scientists use a logical process of deduction when they infer from a proposed cause to a predicted effect by asking an if-then question -- If this was the cause, then what effects should we observe? -- that produces a theory-based prediction (made before the observed effects are known) or postdiction (made after the observations are known).  A prediction and postdiction are logically equivalent, if each is obtained by valid deductive logic.
    Scientists use retroduction when, after observations are known, they infer from an observed effect to a proposed cause by asking a reversed question:  These are the observed effects, so what might the cause have been?  During retroductive inference, scientists try to find a theory (by selecting an existing theory or inventing a new theory) whose postdictions will match the known data.
    Retroduction is one type of hypothetico-deduction, which is a general process of logical inference that uses degree of agreement (do observations agree with predictions?) to evaluate a theory, and uses degree of predictive contrast (what differences occur in the predictions of different theories?) to compare and evaluate competitive theories.  { For details, check Section 7G [@]. }

    But in the two types of science, data is different.
    In operations science, in experiments (and sometimes in field studies) observations can be repeated and variables can be controlled.
    But in historical science, repeatability and controls are impossible (except for decisions about which phenomena and characteristics to observe), and a deduction must be made after an event has occurred.  { But deductions can be made either before or after event-data is known, to generate predictions or postdictions, respectively. }  Since these data limitations occur in all areas of historical science, including astronomy, geology, and evolutionary biology, they pose no special problems for design.

    Regarding the relations and timings of deduction and inference, our expectations are similar for historical scientists and for other historians.  In all areas, including science, we expect historians to construct descriptions of what happened in the past and to propose explanatory theories for how it happened, but we don't expect them to predict what will happen in the future.

    Personal Agency
    In both historical science and operations science, in some situations we must consider the effects of personal agency because "what happens" depends on the decisions and actions of individual agents.  In these situations our ability to make precise predictions will usually decrease due to the unpredictability of individuals.  But similar methodological problems exist in design and in other scientific theories that postulate action by agents.
    In the production of a designed feature, there are two opportunities for agency: in the design, and the design-directed action.  The agents for these two phases could be the same (as implied in Section 7A) or different.  For example, engineers could design an airplane, then factory workers actually build the plane.  Or, God might design a "plan for action" and then use a human to carry out the action.  In fact, this type of dual agency -- combining the supernatural and natural, with God and humans working together -- plays an important role in theology and (I think) in life.

    Supernatural Agency
    In historical science, supernatural agency and natural agency are methodologically similar.  In each case a past occurrence of design-directed action can be inferred when careful examination of a feature reveals observable signs of design, even though (since it occurred in the past) the agent and action have not been directly observed.  In each case it is difficult to make precise theory-based deductions (as either predictions or postdictions) but it is possible to scientifically justify a retroductive inference that "design-directed action by an agent has occurred."  The logical process of inference is similar, whether the agency was natural or supernatural.
    If an event involving agency was not observed, there are two possibilities.  Perhaps the agent could have been observed, but was not.  Or maybe the agent, if supernatural, could not have been observed, even by an eyewitness.  In each case, the agent has not been observed, but observable effects -- which are the foundation of scientific logic -- could be produced by either type of agent.  Therefore, it is not methodologically useful (at least it isn't useful in the "ancient history of nature" situations for which intelligent design is typically proposed) to make a distinction between agents that are unobserved and unobservable.
    But is supernatural action possible?  An atheist and deist and theist, due to their differing beliefs about the existence and activities of supernatural agents, will have different views regarding the possibility of supernatural action.  Since there is no metaphysically neutral way to decide between these views, it may be wise to adopt the non-restrictive policy of Open Science by saying "maybe supernatural action is possible, and maybe it isn't."

    Section 7G [@] contains a deeper analysis of historical science, personal agency, and supernatural agency.  It examines cause-effect principles and hypothetico-deductive inference.  It describes how the process of retroductive inference is affected by predictive accuracy and precision, which in turn are affected by contingency and complexity, empirical and theoretical knowledge, mechanisms and agency.  It explains why, although in historical science there are reasons for caution due to inherent limitations in the available data, scientists can develop methods for reducing the practical impact of the limitations.  These methods should be critically analyzed, but we should not automatically eliminate historical science (whether it proposes design or non-design) from being authentically scientific.

    Evidence and Testing
    Careful observation, combined with intuition and analysis, can lead us to recognize distinctive signs of design, such as special characteristics (like prime numbers) or purposeful functionality (like a camera that makes a photograph).  Del Ratzsch describes design in terms of the counterflow that occurs when events "have been pushed in a direction contrary to the normal flow of nature."  He uses a diesel bulldozer as an example of an object with clearly observable counterflow marks that "cannot or would not be produced by nature."  These signs of design provide evidence indicating that the bulldozer was produced by design.
    When is it logically justifiable to make a claim for design?  There is evidence for design when production by undirected natural process (by non-design) is not a plausible explanation for a particular feature, when it seems more likely that the feature was produced by design-directed action.  A feature was produced by either design or non-design, which are mutually exclusive.  Therefore, when the evaluative status of non-design decreases, the status of design increases;  evidence against non-design is evidence for design, so we can use the predictions of non-design theories to test and evaluate a design theory.  This relationship between predicting (by non-design) and testing (of both non-design and design) is unusual, since most theories are tested by using their own predictions.  But this methodology -- of supporting a claim for design by gathering evidence against non-design -- is logically valid because the correct theory must come from within one of the two mutually exclusive categories, design and non-design.

    Testing and Falsifying
    Can design be proved or disproved?  No.  Section 7B explains why, since we cannot falsify all possible theories that claim non-design, we cannot prove design [@].  Similarly, design cannot be disproved.  This is not a cause for concern, however, because it is impossible to prove or disprove any scientific theory by using formal logic.  But even though we cannot formally falsify design (or any other theory), it is possible to scientifically falsify a design theory, to develop a rationally justified confidence that a theory of design is false.  Or we could be scientifically confident that a design theory is true, or that design is the best of the currently available explanations.  Or we might simply conclude that design, as a potentially plausible explanation, is worthy of further development.
    Critics of design tend to focus on falsifiability, with two contrasting concerns that form an interesting combination.  First, they worry because design cannot be formally falsified.  But non-design also cannot be falsified, so they worry because design cannot be proved.  Somehow, the lack of symmetry in their own concerns (with unfalsifiability in design being criticized, while unfalsifiability in non-design is praised) doesn't seem to be a cause for concern.
    When we're thinking about the testability of design, focusing on falsifiability is not the most practical approach.  Instead, it is more useful to ask, Can the evaluative status of a design theory be changed (either up or down) by empirical data?  This question, which is a sensitive and logically valid way to determine whether a theory is empirically responsive, can be answered YES for many theories of design, so these theories can be scientifically evaluated based on empirical data.  Critics confirm the testability of design when they try to show, using empirical evidence, that a particular design theory is less plausible than is claimed by its proponents. {example}  If the design theory was not empirically responsive, if it was immune to evidence and could not be tested, such criticism would serve no practical purpose.

    Design uses Scientific Logic
    Design theorists oppose the restrictions of MN-science, but they use the logical methods of MN-science.  They begin with MN, but don't insist on always ending with MN.  They use conventional methods of scientific analysis, such as the hypothetico-deductive reasoning (done by comparing theory-based deductions with observations) that serves as a "reality check" for empirically evaluating the plausibility of a theory.  They think that -- if scientific evaluation shows theories of non-design to be implausible -- it is rational to reject these theories instead of insisting (as in MN-science) that a non-design theory must be accepted anyway.
    Conventional scientific methods, applied with an open mind, are sufficient to provide logical support for design.  In fact, in some areas of current MN-science, logical methods for detecting design are now commonly used.  For example, theories of design are being proposed and tested when forensic scientists investigate crimes, and when astronomers search for radio signals designed by intelligent extraterrestrials.  Similar methods are being used, and further developed, by design theorists.

    Mechanisms and Matching
    For theories that propose a detailed causal mechanism, we can make detailed predictions by using deductive logic, by asking an if-then question, "If this theory is true (so the proposed mechanism is operating), then what should we observe?"  But a basic theory of design does not propose a detailed causal mechanism;  it claims that a feature was the result of design, but makes no claims about the designing agent or the directed action that produced the feature.
    Scientists generally prefer a theory that includes a precisely detailed mechanism, but this is not required for scientific acceptance.  And a mechanism is not required for scientific utility.  As discussed above, even though design theories don't propose a detailed mechanism, empirical evidence that is analyzed by conventional scientific logic can support claims for design. 
    There is no need for detailed predictions, unless in addition to expecting that a design theory should be tested for what it does claim (that design occurred), we also demand that it must be tested for what it does not claim (that it can explain the details, the "how, when, why, and who" of the design-and-production process).  This extra demand is not needed to evaluate a claim for design, and it is not reasonable.  Why?  For the same reason we don't demand that officers in a police department should never turn a case over to the Homicide Division until they already know the details and have identified the murderer.  An exploration of design in any area (in homicide, radioastronomy, origins,...) is a two-step process:  first ask "Was there design-directed action?" and then investigate the details.
    We should recognize the limited claims made by a design theory, so we can evaluate design based on what it is, not what it isn't but never claimed to be.  This recognition is important, since it will help us think about testability in a way that is logically appropriate, that achieves a match between the claims made by design and the methods used to justify these claims.

    Supplemented Theories
    As explained above, a basic "design only" theory should be considered scientifically acceptable, whether it's proposed in astronomy (where a signal containing prime numbers would be recognized as design, even if nobody knew who the designers were) or to explain biological origins.  But if we want an origins theory that is more complete, a basic design theory can be supplemented with details about the designer's identity and actions.
    For example, a theory proposing design for the origin of increasingly complex life on earth could be supplemented with proposals for old-earth creation by God, young-earth creation by God, creation by another supernatural agent, or construction by natural extraterrestrial agents.  Each of these five explanations (the basic theory and the four supplemented theories) can be evaluated independently on its own merits, to generate five different estimates of plausibility, one for each theory.  Supplementation can significantly affect the scientific content and plausibility of a design-and-creation theory, as discussed in "The Many Meanings of Creation" in Section 6B [@].
    Supplementation also affects our judgments about how "scientific" a theory is.  Some arguments for "design as science" also apply to "creation as science" but others do not apply.  And the question being examined in this section is whether design (not creation) is scientific.

    Design and Creation
    What is the relationship between design and creation?  They are related, but are not the same.  They are logically connected, but only partially, since a theory of origins design can be (but doesn't have to be) supplemented to form a theory of theistic design-and-action.  They are theologically correlated, but only partially, since most advocates of design (but not all) are Christians.  And design is not the same as "young earth" creation, since two different questions (Has design occurred? How old is the earth?) are being asked.  { Also, claims for design are based on scientific evidence, while defenses of yeC, especially within the Christian community, often rely heavily on Biblical interpretation. }
    Two important principles -- 1) each theory should be carefully evaluated based on what it claims, no more and no less, and  2) design can involve agents and actions that are either natural or supernatural -- are discussed in this subsection:

    1) When theories are compared, we should notice both similarities and differences.  For example, when we compare typical theories of old-earth creation and young-earth creation by carefully examining the individual components within each theory, we see some similarities (e.g., both agree that irreducible complexity seems to exist) and some differences (e.g., they disagree about young-earth flood geology).  Each of these components, irreducible complexity and flood geology, should be evaluated separately and independently.  An overall theory of creation that combines many components, that makes many claims, should be evaluated with a wide focus that includes all of the claims, as explained in Section 6B [@].  But a theory of design that makes one claim, such as "the design of irreducibly complex systems," should be evaluated with a narrow focus that considers only this claim.

    2) What are the implications of design?  If a feature was not produced by undirected natural process, what are the alternatives?  An agent of "design and directed action" could be a nonhuman animal (as in ant hills, bird nests, and beaver dams), a human, an extraterrestrial space alien, or a supernatural being.  For each major area of origins, design doesn't necessarily mean creation:
    a) For biological evolution, the "production scenario" most commonly imagined by naturalistic design theorists is for directed panspermia, with the evolutionary development of life on earth being stimulated and guided by natural extraterrestrials who became highly evolved before the advent of complex earth life.
    b) For the first life, current design theories claim that a natural formation of carbon-based life (involving DNA, proteins, water,...) is highly implausible.  What are the alternatives?  Maybe God designed the universe so it would naturally support life, but would not naturally produce life, so God miraculously created life on earth.  Another design theory, nontheistic and naturalistic, might propose that life did arise naturally, but it was life of a type (and in a setting) we cannot now imagine;  then this life evolved to a level where it could design and construct the familiar carbon-based life inhabiting the earth.
    c) For our universe, with its life-allowing properties, a design theorist with a pantheistic (or panentheistic) worldview might propose that a universe can somehow evolve into a unified super-consciousness that is intelligent, active, and powerful.  Perhaps this happened in the distant past, and a previous universe has already designed and constructed new universes, including the one we now inhabit.

    A basic design theory -- before it has been supplemented in ways that are theistic, naturalistic, or pantheistic -- is limited to claims that can be scientifically evaluated.  Michael Behe clearly explains the limits of his "design only" claims, in a summary of ideas from pages 245-250 of his 1996 book, Darwin's Black Box:
    Although I acknowledged that most people (including myself) will attribute the design to God -- based in part on other, non-scientific judgments they have made -- I did not claim that the biochemical evidence leads ineluctably to a conclusion about who the designer is. In fact, I directly said that, from a scientific point of view, the question remains open. In doing so I was not being coy, but only limiting my claims to what I think the evidence will support. To illustrate, Francis Crick has famously suggested that life on earth may have been deliberately seeded by space aliens (Crick and Orgel 1973). If Crick said he thought that the clotting cascade was designed by aliens, I could not point to a biochemical feature of that system to show he was wrong. The biochemical evidence strongly indicates design, but does not show who the designer was.  {from Philosophical Objections to Intelligent Design: Response to Critics}
    Here, Behe is explaining why -- even though his theory claiming that "design has occurred" can be scientifically evaluated -- he is not claiming "creation has occurred" because, based on the evidence he is considering, this claim cannot be scientifically evaluated.

    Freedom and Positivism
    Scientists cherish their freedom of thought.  They don't want to be restricted by "rules" for doing science.  They do want the freedom to pursue explanations in any way they think will be effective.
    Consider, as an illustration, the methodological philosophy of positivism, and how scientists in the 1700s responded to these proposed restrictions.  A central principle of positivism is the assertion that an authentically scientific theory should not propose the existence of entities, actions or interactions which cannot be directly observed.  For example, behaviorist psychology avoids the concept of "thinking" because it cannot be observed.  A positivist would approve.  And in the early 1900s, Ernst Mach urged the abandoning of atomic theory because it proposes the existence of "electrons" and other unobservable entities.
    What has been the modern response?  Although behaviorism was dominant in American psychology for several decades, since the 1950s its influence has been surpassed by a less restrictive cognitive psychology (whose focal point is the process of thinking) that provides a liberating perspective for scientists.  And atomic theory is alive and thriving.  Most modern scientists believe that thoughts and electrons exist, even though they cannot be observed, because effects that can be observed are most satisfactorily explained by proposing the existence of thoughts and electrons.  { In the same way, scientific logic could lead us to infer that an observed effect was produced by the action of an unobserved designer. }  Many modern scientific theories include unobservable entities (photons, electrons,...) and interactions (electrical fields and forces,...) among their essential components.  Faced with a choice of "behaving as they should" (according to positivists) or being effective, scientists have chosen effectiveness and freedom.

    When this "freedom of thought" principle is applied to open science and design, an important question arises:  If scientists prefer freedom, why is MN -- which restricts freedom -- a commonly used methodology?  There is a simple explanation:  Most scientists work in areas that are not affected by MN restrictions;  in the few areas that are affected, those favoring the status quo hold positions of power, and they have a vested interest in maintaining MN so they can use it to censor their critics in an effort to protect their paradigm and its core theories.

 
    Can a design theory be scientific?
    What is science?  In the past, attempts to define demarcation criteria -- which claim to capture "the essence of science" and therefore to clearly distinguish science from nonscience -- have not been satisfactory. 
    Despite these difficulties, some critics of design want to use methodological naturalism as a decisive demarcation test.  They ask one question, "Does it violate MN?", and consider the case to be settled.  But is it really that simple?

    This section has examined the main arguments for enforcing MN and excluding design from science.  Initially, these arguments may seem credible, but when we inspect more closely the logic is less impressive, and it seems less reasonable to exclude design from science.
    Here is a brief review of the first part of the section:  a Closed Science, restricted by MN, might guarantee that science will reach false conclusions;  an Open Science allows, but cannot guarantee, reaching correct conclusions;  a theory of design can be scientifically useful (because it might be true, it can promote a more accurate evaluation of non-design theories, and it can stimulate creative thinking and action by proponents of either design or non-design);  design is not a science stopper (in the actual practice of science), should be evaluated based on what it is now (not what other theories were in the past), and should not be excluded by citing the status quo (by assuming that current methods are necessarily the best methods) or by the verbal equivocation of using "natural" with two different meanings;  there is no incompatibility between science and occasional miracles;  and since design does not require miracles, it does not even explicitly violate MN.

    When examined closely, a few of these arguments (such as those about "natural science" being "natural" by definition) seem rather trivial.  Other ideas, especially those encouraging us to think about the practical effects of an open science and a closed science, are more worthy of serious consideration, if only because they can stimulate productive thinking and interactions.  Some concerns, involving scientific methods of theory testing and evaluation, seem especially important and interesting.  These methodological concerns have been discussed in ten subsections:  Observable Effects, Historical Science, Personal Agency, Supernatural Agency;  Evidence and Testing, Testing and Falsifying, Design uses Scientific Logic;  Mechanisms and Matching, Supplemented Theories, Design and Creation.  Here is a summary of the main ideas:
    because an unobservable cause can produce an observable effect, scientific theories can postulate the existence of a cause that cannot be directly observed;
    in logical methodology and use of data, a design theory is similar to other theories in historical sciences;  strategies for coping with the uncertainties of agency are similar, whether a personal agent is natural or supernatural;
    the main evidences for design are observable "signs of design" that probably could not be produced by undirected natural process;  since design and non-design are mutually exclusive, their plausibilities vary inversely, and testing for non-design is a way to test for design;  although design cannot be proved or disproved using formal logic, scientists can develop a rationally justified confidence that design (or non-design) is the best currently available explanation, or is at least a reasonably plausible explanation;  a theory of design is empirically responsive, and is therefore testable, if its evaluative status can be changed (up or down) by empirical data;  when critics try to empirically refute a design theory, they are confirming that the theory is scientifically responsive and testable;
    scientists who propose design use the conventional logic of MN-science, but question the wisdom of restricting science to the conclusions required by MN;  in some areas, such as forensic science, methods for testing design theories have been developed and are commonly used;
    a basic design theory does not propose a mechanism for the directed action that produced a designed feature, but a mechanism is not required for scientific utility;  a design theory should be tested for what it claims (that design occurred), not for what it doesn't claim (that it can explain the details);  a basic design theory can be supplemented (with details about when, how, why, who,...) in many ways (theistic, naturalistic, or pantheistic), and each theory (basic and supplemented) should be evaluated on its own merits;  theories of design and creation can be related, but are not the same, and design does not necessarily imply creation;  a basic design theory is limited to claims that can be scientifically evaluated.

    Conclusion
    Can a design theory be scientific?  This section begins with reasons to say YES, and then explains why reasons for saying NO do not seem logically justified.  The more closely we examine arguments for enforcing a rigid methodological naturalism in science, the better "design as science" looks.  This suggests that, instead of using MN in a futile effort to separate science from nonscience, for each theory of design we should ask, "Is it scientifically plausible?" and "Is it scientifically useful?"    These questions are explored in Sections 7B and 7D.
    7B:  Based on their analysis of observations, some scientists are wondering whether a theory of "intelligent design and design-directed action" might be a plausible explanation for the first life, complex life, or the universe itself.  Even though proof is impossible, can we develop a scientifically justified confidence about the plausibility of a design theory?
    7D:  In our search for truth, is MN always helpful?  Should we reject a theory of design before looking at the evidence, or should we consider the possibility that design is a potentially reasonable explanation that is worthy of further development?  What are some benefits of an Open Science that has been liberated from the restrictions imposed by MN?