Although national events continue to underscore the strained relationship between belief and evidence, we, as human beings, persevere in our search for knowledge. Not only is knowledge power, but knowledge is valuable in its own right.
Knowledge takes on various forms. We know, for example, who raised us, what our favorite food is, what pain feels like, how to read, and that dogs bark. In the first case, our knowledge is about a person; in the second, a physical object; in the third, an experience; in the fourth, an activity; and in the fifth, a fact.
A fact is most often referred to as a true proposition. We spend much of our existence trying to discern what is and is not a true proposition. However, knowledge is not as easy to come by and mankind has often taken some bizarre detours.
One such detour was the ancient Babylonian’s obsession with hepatoscopy, which is divination through inspection of the liver. Coupling their understanding that the liver was the organ richest in blood with the belief that blood was the life force, the Babylonians developed an entire religious sect around the study and sacrifice of livers.
The ceremony began with the sacrifice of a sheep and the subsequent detailed examination of the slaughtered animal’s liver. Carefully and respectfully, they would inspect its shape, its blood vessels, and its lobes to see what it disclosed about the future. Decisions involving the military, agricultural and other areas of importance were made based upon what they found. This ceremony was considered so reliable and important that only royalty was allowed to perform it. The inspection of the sheep’s liver by a duly appointed seer was considered a solemn act of state. Over time, certain features of the liver were believed to foresee specific events. Over 700 clay tablets were created memorializing prophesies all based on a sheep’s liver. Generations of seers were taught and trained to carry on this holy tradition, which no one was allowed to question. Luckily for the seers who dedicated their entire lives to this tradition, no one was ever asked to explain the correspondence between a sheep’s liver condition and human affairs.
Although hepatoscopy is no longer with us, the second Babylonian obsession, astrology, is alive and well in 2019. They believed that each planet housed a different god and each played a separate role in our lives. But neither the ancient Babylonians nor present day astrologers are able to explain in scientific terms the cause and effect of heavenly bodies on us.
Although you may agree with me that the claims of hepatoscopy and astrology can be easily dismissed, we are forced to judge on a daily basis factual claims whose truth or falsity is not readily apparent. As I suggested in earlier columns, our only recourse in separating fantasy from reality is to carefully examine the evidence presented for each proposed truth.
But how much evidence do we need before we can declare that we “know” something? Do we require absolute certainty? Do we need to have proof beyond a shadow of doubt? And what does that mean anyway? If you’ve ever served on a criminal jury, you might recall the District Attorney reminding you that the State is not expected to prove its case “beyond all doubt” since that is impossible. On the other hand, the more evidence we have, the more comfortable we will be in justifying our belief in the proposition in question.
When I was in graduate school, I had the pleasure of taking a course about the great American philosopher, Charles Sanders Peirce. My professor, Dr. Elizabeth Kraus suggested that Peirce’s greatest insight was his insistence that we should feel comfortable with the beliefs we eventually embrace having arrived at them because they where an “inference to the best explanation.” So, for example, it’s possible that you’re living in a computer-generated dream as envisioned in the movie, The Matrix. However, we can reasonably say that we are not living in such a situation because The Matrix hypothesis does not provide the best explanation of our sense experiences.
The acceptability of a theory is determined by the amount of understanding it produces. In turn, “understanding” is a direct result of how well it systematizes and unifies our knowledge better than a counter hypothesis. For example, man-made global warming has been verified by so much scientific data and by so many sources. Even if we can’t say beyond all doubt that its conclusions are true, we can sensibly hold that it is by far the best explanation for all the information we have.
Consequently, to deny its truth is literally “unreasonable.”
But what about the claim “everybody is entitled to his or her own opinion?” That is certainly legally accurate, but is it okay to believe things merely on a whim? Distinguished mathematician W.K. Clifford says no, “it is wrong always, everywhere, and for anyone to believe anything on insufficient evidence.” Philosopher Brand Blanshard goes even further by calling the publication of beliefs without evidence “immoral.” For both these thinkers, the more important the decision the more egregious the crime when they are not guided by a good faith effort to find the truth.
So, in our current political climate, where facts seemingly no longer matter, can we really “know” anything for certain? The answer is both yes and no. Since our only method of comprehension is induction, there is always the remote chance that we get things wrong. However, when we make a good faith, unbiased, and thorough effort to find the truth, when we sift carefully through the evidence to test the bounds of our conclusions, then we can confidently say that we “know” something to be true.