I am a philosopher by nature. This should come as little surprise to those of you with whom I have conversed at any length or who have even a passing familiarity with My works to date. I took a minor in philosophy at a small (Christian) college and have been more-or-less actively involved in the act of, well, philosophizing, ever since.

Lately I have been philosophizing regarding the nature of proof. (More simply I could say that I’ve been thinking about the nature of proof, but why use four syllables when eight will do nicely?) What is proof and what does it mean to prove something?

Let’s take a look at a few different types of proof and how they are used. Certainly there are more types, there are gradients between the types, and not everyone is going to agree on these definitions. (Also keep in mind that I never graduated law school. I am not a legal professional though I did work as a paralegal for a time, and nothing I say should be considered legal advice.)

Mathematical Proof

There is a type of proof known as mathematical proof or logical proof. It is found, as might be suggested by that name, most often, though certainly not exclusively, in mathematics and logic. It includes, for instance, statements such as “2+2=4” or tautologies like “all bachelors are single men.” Syllogisms such as the basic “All a are b; Q is a; therefore Q is b” are also in this realm, along with other more complex forms of arguments.

Such “proofs” are, in My mind, the highest form of proof. They are true absolutely … with the caveat that they are only true if both you and the person you are attempting to convince have a shared understanding of the meaning of the symbols and/or words involved. There are, of course, false statements such as “2+2=56” or “all athletes have below-average intelligence,” but those are readily detected and disproven (one more easily than the other, of course).

But it remains true that these things are true or false within a predefined and agreed-upon system. Take the concept that within the limits of Euclidean geometry, it is true that parallel lines never intersect. In non-Euclidean geometry, for instance, elliptic or hyperbolic geometry, that statement would become false.

Non-Euclidean geometry had a rather significant effect on Kant’s popularity as well, as he considered (Euclidean) space to be one of the categories of knowledge innate to every man, or a priori knowledge, deduced from reason alone. This causes some to doubt the very concept of a priori knowledge and transcendental idealism postulated by Kant, which included such knowledge of other fields including metaphysics. Others, however, see no necessary contradiction here.

Reasonable Doubt

A phrase common with many Western law students (or watchers of police procedural dramas on television) is the “proof beyond a reasonable doubt.”  This is the level of proof needed to convict the accused of a criminal offense.  A hypothetical example may help.

I am found to be on heroin and a subsequent search of My person and apartment turns up 2kg of the drug; in the United States, this is a Federal offense which can warrant from 10 years to life. I claim that an alien teleported into My locked apartment, paralyzed Me, dosed Me, left the drugs under My bed and then disappeared without a trace. I think that reasonable doubt as to My guilt would be fairly unlikely in such a case (though I may try to go for an insanity defense).

It is this level of proof which I personally use whenever I say that I am “certain” of something.  I cannot prove in a mathematical sense that I am under the control of incorporeal space aliens who are using Me to lay the groundwork for their coming invasion.  Neither can you disprove it – in a mathematical sense.  “Beyond a reasonable doubt,” yes, I tend to think that I would end up on the short end of that discussion stick.

This is the level at which I usually have religious debates and where I find that many atheists find themselves.  I cannot “prove” that god does not exist, even laying aside the semantic issues I have with even the word itself.  Yet I am convinced “beyond a reasonable doubt” of the non-existence of whatever you mean by that word unless you mean something very, very different by it than what is commonly meant.

Preponderance of the Evidence

This is also a legal term of art, used mainly in civil trials.  Basically it means that the plaintiff in a civil suit must prove that his (or her) case is more than 50% likely to be true.  Not beyond a reasonable doubt, simply that it is more likely than not to be the case.  Again, an example may help what I mean.

Let’s say that the Robertson family is suing Acme Electrical because of faulty wiring in the new home they just bought.  Their house burned down and investigators reported that faulty wiring was the cause.  Acme contends that the Robertson’s son modified their wiring as part of a scientific experiment to try and open an inter-dimensional wormhole.  (Fortunately, the entire Robertson family escaped without injury, although Mrs. Robertson fled onto the street dressed only in her little yellow nightie that only covered … but I digress.)

The court is tasked with determining whether the actual culprit was Acme or the Robertson kid.  Laws in many states differ, with some saying that unless Acme was guilty by a “preponderance of the evidence” then they are assigned no liability, while others ask how much (if any) liability Acme should be assigned for the pile of ashes that is all that remains of the Robertson home.

Myself, I consider most matters of personal choice to be at this level. If I have a choice between having hamburgers or pizza for dinner, I’ll weigh the pros and cons of each and whichever one seems more tasty to Me at that point is what I’ll cook. If I’m voting for a candidate for political office, I’ll look at each of them and vote for the one who disgusts Me the least. This also affects My choices in the area of morality, in that it often comes down to a choice between two actions neither of which seem attractive, but I choose the one that I can live with best.

I will debate politics and morality with somewhat more vigor than I will debate culinary tastes, of course! At the end of the day, however, I realize that each of those is a personal choice. I respect each person’s conscience in such matters and insist that Mine be respected in return.

Conclusion

As I said earlier, many people have different levels of proof that they require in order to justify an adherence to certain beliefs. Some people are content with making theism a matter of personal taste and go to whatever church or synagogue or temple their parents went to and believe whatever they believed.

I find it interesting that for most people who believe what they believe on a preponderance of the evidence, the requirement that they have for people who believe something other than that which they believe seems to be much closer to mathematical proof. “I don’t have to prove it, it’s in the Bible and I believe in the Bible and that settles it” becomes, regarding other religions, “Why do you believe something so stupid as that? You can’t prove that and the Bible says you’re wrong and I believe in the Bible and that settles it.”

This does not characterize all Christians (or Muslims, or Jews, or Hare Krishna devotees, or whatever). Most religionists honestly feel that their holy book(s) are the best and contain the best proofs. When a Muslim claims that Muhammad predicted global warming, a Christian will deny that while at the same time claiming that the OT has “clear” prophecies of Jesus. If a Christian says that Jesus came back from the dead, then Muslims laugh and call them silly but then claim that the Koran accurately describes embryonic development. Of course they both ignore the mountain of ‘evidence’ for reincarnation as found in Hinduism, as well as indications that the Mahabharata may accurately record events which predate Genesis.

There are some religionists who actually do think that they have a mathematical proof of god.  (And that starting with St. Anselm way back when, actually … though Aristotle may have leaned in that direction if I recall aright.)  Some are willing to concede having only a “beyond a reasonable doubt” sort of ‘proof.’ That’s the level that I require.

I suppose that Christians and I will simply have to disagree on whether people coming back from the dead, a global flood uncorroborated by the physical evidence survived only by one family in a floating box full of animals that did not eat them (or each other), an exodus from Egypt unsubstantiated by any traces of either their captivity or their departure en masse (or the alleged plagues that preceded said departure), a talking donkey (a la Shrek maybe?), a guy who stopped the sun from going around the Earth (so much wrong with that statement) … We will have to disagree on whether those and other parts of their scriptures that are more reminiscent of fairy tales than serious religious philosophy (though the difference is often hard to discern) would lead a “reasonable” person to hold a “reasonable doubt.”

Thank you for thinking.