Sunday, May 21, 2017

Extraordinary Claims and Extraordinary Evidence

"Extraordinary claims require extraordinary evidence" is a phrase that was popularized by Carl Sagan but has its roots from at least the 18th century Enlightenment when the miracles of Christianity were being questioned by certain intellectual thinkers of the day. The most famous Enlightenment critic of Christianity was probably David Hume who wrote an essay called Of Miracles in 1748 where he states, "Suppose, for instance, that the fact, which the testimony endeavours to establish, partakes of the extraordinary and the marvellous; in that case, the evidence, resulting from the testimony, admits of a diminution, greater or less, in proportion as the fact is more or less unusual."

At first this statement may sound reasonable. For instance, I am more likely to believe you if you tell me you had breakfast this morning than I would believe you if you told me that you levitated off the ground this morning without anything holding you up. But does the fact that I believe you if you say you did something ordinary and I don't believe you if you say you did something extraordinary support the statement that "Extraordinary claims require extraordinary evidence?" Actually, it doesn't. Although I may believe that you ate breakfast this morning, I must obtain supporting evidence if I want to actually determine whether or not that fact is true. If you have cleaned up your kitchen, such evidence may be hard to find. I might have to pump out the contents of your stomach, for instance to see what you ate and when you ate it. It is one thing to say that I believe you ate breakfast because it is an "ordinary" event, but it is quite another to actually find enough evidence to validate your claim. My point is that actual validation of any event requires sufficient evidence.

It seems to me there are two major categories of "extraordinary" claims that need to be considered. The first would be a claim that can be tested in a controlled environment, like if someone claimed to be able to predict the outcome of rolling a six sided die 90% of the time, or if someone claimed to be able to levitate at whim. Those kinds of miraculous paranormal assertions can be easily tested, and to my knowledge, have never been validated as true. But the second category of "extraordinary" claims, which would include the miracles believed by Christians to be true, are events that occured only once in the past, and can not be tested in a controlled environment. I can't imagine any amount of evidence would convince Hume that such a miracle has occurred. He states, "A miracle is a violation of the laws of nature; and as a firm and unalterable experience has established these laws, the proof against a miracle, from the very nature of the fact, is as entire as any argument from experience can possibly be imagined." For this second case, I believe that the claim that "extraordinary claims require extraordinary evidence" is really just a presumptuous statement, and that no amount of evidence would ever convince the skeptic that a past single miraculous event occurred.

Let's consider an example of a hypothetical past miraculous event. Since skeptics claim that God must not care about amputees because they know of no documented case where an amputee had her limb grow back, let's suppose there was such a case. Suppose a particular person with an amputated arm wakes up one morning and the arm has completely grown back. The person, her spouse, the doctors, and her friends all claim that the last time each of them saw her she did not have an arm and now she does. Would that eye witness testimony be enough to convince the skeptic that a miracle has taken place? I don't know if it would or would not, but I do know that such eyewitness testimony is certainly not "extraordinary evidence." It is just plain old eye-witness, first person, evidence. So either the statement that "extraordinary claims require extraordinary evidence" is false or there is no reasonable evidence, including tremendous corroborated eyewitness testimony, that would convince the skeptic a miracle has occurred. As such, the proposition that "extraordinary claims require extraordinary evidence" seems totally disingenuous when it comes to any single past miracle. It seems to be simply a well-crafted phrase that sounds scientific but is not, and which allows the skeptic to dismiss any amount of supporting evidence. After all "extraordinary" is such a vague word that it is easy to dismiss all evidence as falling short of that nebulous standard.

There are examples in the Bible of extraordinary events with amazing corroborating eyewitness testimony that were dismissed by those who already had their minds made up. John 9 tells the story of a man who was blind since birth whom Jesus gave sight. The skeptical religious leaders questioned the man and his parents to see if he was really blind since birth and if Jesus had given him sight. Although he confirmed that was the case, and his parents confirmed he was their son who was blind from birth but could now see, the leaders refused to believe the truth that was right before them.

Another example of those refusing to believe that miracles could occur despite the evidence is found in Luke 16 where Jesus tells the story of a rich man and a poor man, Lazarus, who would beg for food at the rich man's gate. Upon their death, the rich man is in torment but can see Lazarus far away in comfort. The rich man asks Abraham to please send Lazarus back to his father and brothers to warn them of the reality of the afterlife so that they will not have to be tormented. Abraham's response to the rich man is, "If they do not listen to Moses and the Prophets, they will not be convinced even if someone rises from the dead." If they don't believe the testimony they already have, then no amount of "extraordinary" evidence, even someone coming back from the dead, would change their mind.

As a scientist, I am skeptical about everything. I don't believe in fairies, unicorns, extrasensory perception, telekinesis, horoscopes, or anything like that. I don't believe in them, not because I require extraordinary evidence, but because I require just sufficient evidence. Rather than ask that some unattainable "extraordinary evidence" be presented as an excuse to dismiss any supernatural act, I instead want to carefully examine the evidence and to search for a conclusion that best explains all the evidence without, a priori, ruling out a conclusion based simply on my presuppositions. In Sir Author Conan Doyle's The Sign of Four, Sherlock Holmes provides a better rule for determining whether or not a miracle may have occurred in the past when he says, "How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?"

Although I don't believe in any of the above phenomena because of the lack of evidence, I do believe there is plenty of sufficient evidence to accept the validity of certain past miraculous events including the resurrection of Jesus from the dead. The recent movie, The Case for Christ tells the true story of Lee Stobel, an award-winning journalist and skeptic who was willing to follow any sufficient evidence to find the truth. Unlike David Hume or Carl Sagan or others who make statements requiring an unattainable level of proof, a good scientist or detective or journalist will ask for sufficient evidence that can explain all of the objective facts and be willing to follow the evidence to even an improbable conclusion. Some of the most famous scientific discoveries have been made because of that mind-set. The veracity of all truth claims can be determined with sufficient evidence, and that evidence need not be "extraordinary" even for "extraordinary claims." Instead, it needs to be the same kind of first hand eye-witness or clear forensic evidence or even circumstantial evidence that clearly dispels all other reasonable options and leads to a conclusion that best explains the known facts.


  1. You are to kind to this unscientific rule. The burden of proof is on the presenter, period. I don't care how waco your claim is, if you have ordinary evidence supporting it.

    1. Sometimes a kind response will allow actual dialogue and help others see how illogical their claim actually is. I take it as a compliment that I am kind to this unscientific rule. Thanks.

  2. Nice work Mike...It seems the scientific community at large, peers and colleagues, have little or no rebuttal to your argument against Sagan and Hume.

    Biology claims the arising of a true Von Neumann machine, the cell, without evidence.

    Brian Cox in "Universal" suggests that the entire mass/energy of the universe was contained in a point entity pre-expansion where the average distance between particles was zero. That's about 10**70 ergs (from his number for the mass and E=mc**2).

    In the former the evidence is non-existence and in the latter quite lacking.

  3. This is a really good article, you do not often find such things on such difficult topics. Such articles make you think and look at the familiar things in a new way, which is certainly useful for every person, from time to time. I often order articles or essays on various topics that I do not know, but they help to improve and make me better than I was yesterday. I advise you to write more often, as you will be able to attract a large audience with such articles and thereby be able to make our world a little better.

  4. Very well put Kenneth. My sentiments exactly. I enjoy this blog very much.

  5. Extraordinary evidence for extraordinary claims is not a specific or detail requirement, but I suppose if Sagan, Hume or other Skeptics of their level were asked for a more detail, they could provide a more specific and detail descriptions. Once they did we would have a better idea if they have an appropriate requirement or not.

    Scientist have had a lot of success in coming up with natural explanations for much of what we have observed. So naturally many of them would interpret Sherlock Holmes comment as once you have evaluated all natural explanations that explain the evidence, if the best natural explanation has a significantly low probability, do not think it is false regardless of how low the probability. Alternatively, a committed naturalist could just believe regardless of how small the probability is for the best known natural explanation, the actual natural explanation is unknown and has a high enough probability to be plausible. These sort of approaches can be used to build an insurmountable defense for naturalism.

    From people around the world, there are many claims for supernatural intervention. If a million people buy a lottery ticket that has a chance in one in a million of winning, then the chance of somebody winning is 1-(1-1/1000000)^1000000 = 63%. So it is likely that somebody will win and since most people believe in a god, it is likely that that winning person will think god supernaturally intervened to make them win. But somebody winning such a lottery is expected naturally by random so in this case this evidence alone for supernatural intervention is insufficient. So there is a need for objective and appropriate criterion for substantiating claims for the supernatural intervention.
    Mike can you give a guidelines for criterion you recommend for substantiating claims for the supernatural intervention. If we have an objective criterion, then there would be a basis for differentiating between somebody who is building an insurmountable defense against supernatural claims or somebody who just wants to apply an objective criterion for when they believe that the supernatural intervened. After all there are many different contradictory claims for supernatural intervention so if someone has too low of a criterion, they would end up believing many contradictory things about the supernatural.

    Aside from something like the origin of the universe, claims for supernatural intervention are usually not based on violating deterministic natural laws like your example of levitating which violates gravity. Most claims for the supernatural intervention are of the type where the best natural explanation has a low probability, implying there is no natural explanation, implying the supernatural intervened. For these claims sometimes a probability calculation can be done, but other times there is just a qualitative argument. So it would help to provide guidelines for quantitative arguments and qualitative arguments.

  6. "The veracity of all truth claims can be determined with sufficient evidence, and that evidence need not be "extraordinary" even for "extraordinary claims." Instead, it needs to be the same kind of first hand eye-witness or clear forensic evidence or even circumstantial evidence that clearly dispels all other reasonable options and leads to a conclusion that best explains the known facts."

    I certainly agree with your statement that "the veracity of all truth claims can be determined with sufficient evidence" but I believe this statement needs further clarification. Is it correct that the same standard of evidence is "sufficient" in all similar cases? I don't think so.

    Let's use your example of the reattachment of a severed body part example: Let's first imagine that the severed body part is the tip of a finger. The injured party (the plaintiff) has filed a lawsuit in court, alleging that his injury was due to the negligence of his employer. The plaintiff's lawyer brings to the witness stand eleven eyewitnesses who state that they saw the work accident, they saw the employer's equipment which caused the injury malfunction, and, they saw the plaintiff grab his fingertip, take it with him to the hospital, and all eleven watched as the ER doctor reattach the severed finger tip to the man's finger.

    How likely is it that a jury would find the (for the most part) corroborating eyewitness testimony of the eleven eyewitnesses sufficient to reach a verdict in favor of the plaintiff, the man with the once-severed finger-tip? Pretty good, wouldn't you say?

    Now, here is a second case: Another man presents to the ER, stating he has just suffered an injury, in this case, his right arm was severed just below the shoulder while he is in the woods hunting. Eleven witnesses, all of whom are his hunting buddies, claim that an alien space ship descended over their camp, a three foot, antennae-toting alien beamed down from the space ship, pulled out a laser weapon, and with a green laser, severed their friend's right arm from his body. The space creature was then beamed up to the ship, which flew away at the speed of light. A few minutes later, a second space ship appeared, a second space creature was beamed down to the camp, who reattached the severed arm, apologizing for the behavior of his colleagues in the other spaceship.

    The eleven eyewitnesses and the victim swear on a stack of Bible that their story is true?

    Question: How many juries do you think would believe these twelve guys' eyewitness account? Answer: Probably none.

    But why? We have eleven/twelve eyewitness testimonies in both cases. The testimonies corroborate in the major details, varying only on minor details that do not change the overall account. Why should a jury doubt the testimony of the second group of eyewitnesses?

    Answer: For very extra-ordinary claims, eyewitness testimony is often considered INSUFFICIENT evidence.

    And this is why skeptics doubt the story of Jesus' bodily resurrection. Eyewitnesses claims are NOT sufficient evidence, for most non-Christians, for this very extra-ordinary claim.

    1. You're scenario is totally unlike mine since in mine all the eyewitnesses saw an amputated arm long before the healed arm. But for the sake of argument, now suppose all 11 were told to quit telling that story or we would put them to death. Suppose we tortured them and all they had to do was to change their story to stop being tortured. They have nothing to gain by lying but all 11 are executed just for telling that story. Do you still believe they were lying? If so, what was their motive? So sorry Gary, but once again your hypothesis neglects to take into account the actual facts. Your fantasy hypotheses sound so plausible only because they ignore many aspects of the historical accounts that are crucial to its believability.

    2. Excellent point!

      Now, please provide evidence that even ONE eyewitness to the alleged resurrection of Jesus was given an opportunity to save his life or prevent being tortured by denying seeing a walking/talking/broiled-fish eating corpse.

      You can't, Mike. I know you can't because I was confronted with this same argument when I was still a believer. There are no confirmed cases of any apostle being given the opportunity to spare his life by denying that he saw the resurrected Jesus. Not one. The Catholic Church has many martyrdom tales, some with some really fantastic supernatural details, but the evidence shows that these martyr stories did not appear until centuries after the death of Jesus. For all we know, all the apostles were tortured and killed simply because they were members of a minority religious group that the authorities didn't like. You have no good evidence that they died for refusing to recant.

      However, you are assuming that the only reason that someone would die for his belief in the resurrection is because he truly saw a resurrected body. Remember, that many people today have claimed to have "seen" the Virgin Mary, which most non-Catholics believe are simply illusions or even hallucinations. Many of these very devout people might be willing to die for this belief that they have seen the Virgin Mary. Does their willingness to die for a belief prove the belief is true? No.

    3. Are you denying that the early Christians were persecuted for their faith, were told to stop teaching their doctrine or face punishment, and the there is a historical record of the martyrdom of early Christians including James the brother of Jesus, James the apostle, Paul, and Peter?

  7. The twelve total men and could have colluded together and fabricated the story is plausible explanation so no reason to be convinced their extraordinary claim is true. In a criminal case the judge instructs the jury to not render a guilty verdict if there is a known non-guilty plausible explanation for the defendant, because an explanation is not proven correct until all the alternative explanations are shown implausible. The main debate about the historicity of the Gospels is there an all-natural plausible explanation for these accounts such as a fabrication by the Early Christian church. Eyewitness claiming to have seen the supernatural intervene is not sufficient evidence for supernatural intervention. There are so many religious people who would like to have a supernatural vision so it is naturally expected there will be some that claim they had some supernatural vision. There needs to be sufficient evidence that there is no plausible natural explanation for the claim.

    Now if 2 people claimed that God told them both at exactly 12:32.45 Greenwich Time on the same day that the code to go to heaven is 3532796043453 would be extraordinary if these claims could be verified as truly independent. For instance, the 2 people prior to that point of their reports being recorded were never aware of any information that had the same source through natural means. This would make for no plausible natural explanation. This reasoning uses the well-established criterion of independent corroborating eye witness testimony.

    Historians are impressed with the account of Paul/Saul holding Stephen clothing at the stoning of Stephen in the books of Acts. This is an embarrassing account for the Christian leader Paul to support the stoning of Christians; thus, not expected to fabricated by Christians authors or sources. This reasoning uses the criterion that self-embarrassing reports tend to be more credible because typically there is no self-serving motivation for self-embarrassing reports.

    1. I'm not sure I entirely agree that embarrassing details give more credence to an account, but women discovering the empty tomb is also embarrassing and anti-cultural. There are many details of the accounts that give them credibility.