Tag Archives: Truth

Logic

Spock_at_consoleIn the coming weeks, I want to look at some different arguments for the existence of God. But first, how can you know my reasons for believing God exists are legitimate? Maybe you don’t believe God exists, or maybe you simply don’t know. Likewise, how do I know if your reasons are legitimate? How do we discuss our opposing reasons (for this or anything else imaginable) on a level playing field? With that goal in mind, today let’s start out with a refresher (or introduction) to basic logic. Like a lot of foundational material, it may seem a little dry, but it really is the necessary foundation for any type of critical thinking. Underlined words are key terms in logic.

Let’s start with some clarification. An argument in logic is not a fight or quarrel, but rather a rational though process using a series of statements (or propositions) called premises and conclusions. As such, there are some rules for making sure the conclusions you draw are legitimate. Just like in sports, these rules help ensure that the winner really did win fairly.

Propositions are simply statements that may be either the premises or the conclusion of an argument. While you may be trying to determine a reasonable answer to a question with an argument, you can’t have a question or a command for a premise, so these are always declarative sentences. Not to bring up bad memories of diagramming sentences in grade school grammar, but these statements need a subject and a predicate. The subject is just what you’re talking about, while the predicate is what you’re saying about it. The premises are  propositions that each propose a basis for the conclusion. They give your evidence. Premises can be either true or false.  “The city of Houston, Texas is located in the country of Australia.” is a false premise, while “Mars orbits around the sun.” would be a true premise. These premises use terms that can either be clear or unclear. A term is clear if it can be understood in only one sense. For instance, a person can use the word “hot” to describe: temperature (“It’s hot outside”), attractiveness (“She’s hot!”), or questionable legality (“He wrote a hot check”).  In this case, “hot” has equivocal meanings and wouldn’t be a good term to use in a premise unless we either defined it first, or the meaning was clear from the context. Some terms are not so obviously different  in their meanings, and many a misunderstanding has happened because of this issue of equivocation (using the same term in different ways).

The conclusion either necessarily follows from the premises and the argument is valid, or it doesn’t follow and is invalid. “All men are mortal. Socrates is a man. Therefore, Socrates is mortal.” is a classic example of a valid syllogism. A syllogism is your most basic argument: 2 premises and 1 conclusion showing a clear relationship between 3 terms. If it is true that all men are mortal, and Socrates is indeed a man, then Socrates simply must be mortal. This is an example of deductive reasoning, which generally moves from a universal principle to a specific application. Inductive reasoning, on the other hand, typically moves from specific observations to a more general conclusion. Valid deduction provides certainty in its conclusion, while induction only provides a degree of probability. Just because you’ve observed many similar cases doesn’t mean all cases will be similar (the exception would if you’ve actually observed all cases). Science typically uses inductive reasoning based on specific observations, hence the tendency of scientists and engineers to always qualify what they say with disclaimers.

Understanding the principles of logic is advantageous regardless of your educational background, your culture, or your beliefs because it provides a framework for knowing that what you believe is true. If your terms are clear, your premises are true, and your deductive argument valid, then your position is necessarily true and there can be no argument against it. Likewise, if your opponent’s argument doesn’t have ambiguous terms, a false premise, or a logical fallacy, then, to be honest, you must admit he’s right. The same goes for me. And so we now have a level playing field, with the same rules applicable to and acknowledged by, both sides. Maybe you’ve listened to a talk show where two opposing guests simply stated their own views over and over again and ignored the other side. Or they simply talked past each other louder and louder? Did you walk away feeling like it was just pointless discussing some issues? There is hope, and this is where logic shines. I encourage you to not simply stop at this short  glossary of logic, but to dig deeper, learn it, and apply it in your own life.


Resources:

Socratic Logic, Edition 3.1, by Peter Kreeft, (St. Augustine’s Press, 2010), which served as a reference for much of this. This is an actual logic textbook.

Being Logical: A Guide to Good Thinking, by D.Q. McInerny, (Random House, 2005), is also an excellent and very concise introduction to logic, and well-suited for a first exposure to logical principles.

“Hard Evidence”

Lab Experiment“I don’t think there’s anything he could say that would convince me – I need hard evidence,” said an atheist friend when I invited him to come with me to  a presentation on the reliability of the Bible. That got me thinking about evidence and our desire for more of it. After all, “seeing is believing,” right?

This November marks the 100th anniversary of Albert Einstein publishing his theory of general relativity. Only 10 years earlier, in 1905, Einstein had published not one, but four, paradigm-shifting papers, including his special theory of relativity and his proposal of mass-energy equivalence, from which we get the famous equation E=mc². Since then, his theories have been repeatedly confirmed. Special and general relativity did not simply provide a competing theory compared to classical Newtonian physics; they encompassed Newtonian physics. In relatively weak gravitational fields, special relativity reduced to Newtonian formulas at speeds much slower than the speed of light (our typical earthbound experience). General relativity expanded on that to provide an explanatory framework that could account for objects travelling at all speeds and through any gravitational field. It explained what Newtonian physics could and couldn’t explain. That’s powerful.

How did Einstein develop this powerful theory? Can you tour the lab where he huddled over a workbench full of special scientific equipment, or see the telescope he tirelessly spent long nights peering through, looking for evidence of gravitational lensing, or examine his lab journals of dutifully recorded experimental results? Not really. Einstein worked as a simple patent clerk in his “miracle year” of 1905, and was still doing “thought experiments” when he developed general relativity. He was short on evidence, but long on problems to think through. He proposed 3 scenarios unexplained by Newtonian physics that relativity would need to correctly explain for it to be true: 1) the slight changes in Mercury’s orbit around the sun already observed by others, 2) the deflection of light by the sun that Newtonian physics predicted, but not accurately, and 3) the color change (redshift) of light passing through a gravitational field that was completely unverifiable at that time.[1] While he could compare his theory’s predictions to  Mercury’s orbital changes measured by others, he had no way to confirm the other 2 tests. In fact, the evidence to support his theory only trickled in over many years, the most conclusive confirmations  of it after his death in 1955. Sir Arthur Eddington confirmed the deflection of light by the sun’s gravity in 1919 when he measured the slight curvature of starlight bending in the gravitational field of the sun during a solar eclipse. But it was decades before sufficiently precise measurements could confirm gravity’s miniscule color-shifting effect on light here on earth. In the years since, though, several other effects have verified Einstein’s unproven theory.

In fact, Einstein’s general theory of relativity touches most of our everyday lives  in one very real, but surprising way. Our cars, planes, cellphones, and even wristwatches now have the ability to tell us where we are because a of wonderful cold-war invention called GPS. But engineers designing the GPS satellites originally didn’t think they would need to account for gravitational redshift in the signal timing. This change in color of visible light is actually an effect of time dilation; time actually runs faster in a weaker gravitational field. And so the clock on a GPS satellite will run 38 microseconds faster, per day, than the same clock on earth, which is enough to produce invalid location results. This would also handicap our cell phones that use this precise timing to handle transferring calls to new cell towers seamlessly.

So did the lack of hard evidence in any way detract from the truthfulness of his theory? No, that’s because we don’t create truth, we only discover it. If something is true, it’s true whether we know it or not, and whether we understand it yet or not. The GPS clocks ran faster whether the original engineers admitted it or not, and whether you and I fully understand it or not. Can Christianity be true without measurable, scientific evidence? Absolutely.[2] But there’s a deeper question here. Is experimental observation the only way we come to know truth? No. In fact, the “thought experiments” Einstein relied on were simply exercises in sound reasoning that scientists, mathematicians, and philosophers have used for millennia. As Einstein understood, there are many times where it is impossible to obtain “hard evidence” for something. It may be a unique, non-repeatable event, or it may be something infeasible to test at the present time, but that doesn’t have to stop us from investigating. Albert Einstein didn’t limit himself to experimental evidence, but rather used his mind to go where science couldn’t yet, and he changed the world. Don’t let your desire for a certain type of evidence keep you from investigating the truth of Christianity and changing your world.


[1] Albert Einstein, Relativity: The Special and the General Theory (New York: Barnes & Noble, 2004), p. 87-88.
[2] Not that there isn’t a wealth of evidence for the truth of the Bible, but that’s a subject for another day.

 

“You Can’t Handle the Truth!”

cant-handle-the-truthIn the movie “A Few Good Men”, Tom Cruise and Jack Nicholson famously go back and forth in court with Nicholson finally shouting back from the witness stand the classic line “You can’t handle the truth!” The truth can certainly be a powerful, devastating force at times. But what is truth? The Bible records Pilate asking Jesus that very question almost 2,000 years ago.[1] It’s a big question, but let’s look at one small aspect now.

Truth can be defined as the “ideal or fundamental reality apart from and transcending perceived experience.”[2] This indicates that truth is not subjective since it “transcends perceived experience”. In other words, a statement is true when it corresponds to the object it describes rather than the perception of the observer. Hence, it may be described as objective truth. A color-blind person may incorrectly perceive some colors, but the actual color may be  independently verifiable by the wavelength of light being reflected from an object. That a particular apple’s appearance corresponds to what we call “red” is then objectively true regardless of how, or even if, we perceive it. Likewise, the statement that there is life on other planets may or may not be true; but if true, it will be because of such life existing and not because of our knowledge of it.

What then are we to make of claims today that “everything’s relative”, or that something may be “true for you, but not for me”? First, isn’t it a little ironic to use an absolute term like “everything” to deny absolutes? In fact, both of these statements are actually self-refuting. They “commit suicide” as Greg Koukl would say. What’s implicit in the relativist’s first statements is that everything is relative except their absolute statement. How convenient. But “everything” includes that statement, which puts it in the same category as saying “white is black”. Their 2nd  claim implies that statements may be simultaneously true and false for 2 different people, except for their statement that is assumed to apply equally for everyone. But I can simply apply the claim to itself and say that “true for you, but not for me” is exactly that – not true for me – and ignore it. Ideas have consequences, and because of this self-refuting nature, the concept of relative truth can lead to very real absurdities. Bob may sincerely believe that he can jump off a cliff and fly (without a hang glider or other aid), while his friend John sincerely believes he can’t and pleads with Bob not to jump. Is this a case of “true for Bob, but not for John”? Is John wrong to try to help his friend see his error?  Applying his knowledge of physics and its correspondence to reality to the situation tells John his belief that John will plunge to his death would actually be true for both of them, in spite of Bob’s sincerity to the contrary. That Bob cannot fly on his own is true for all people, for all time, and in all places. That is the nature of truth; we do not create it by our beliefs or statements, but rather discover it.

We can determine when statements about our material world are true (i.e. the law of gravity) by testing them. But what about immaterial truth claims? Are these actual truths or simply opinions? Can we test for truth? Yes. A true statement will always satisfy the 3 fundamental laws of logic[3]:
The law of identity – a statement is identical to itself and different from another statement. A thing is what it is. Saying “Hitler was evil” and saying “Hitler was good” are not equivalent!
The law of noncontradiction – a statement cannot be both true and false at the same time in the same way. For a very clear (if somewhat harsh) verification of this law, the medieval Muslim philosopher Avicenna proposed this demonstration: “Anyone who denies the law of non-contradiction should be beaten and burned until he admits that to be beaten is not the same as not to be beaten, and to be burned is not the same as not to be burned.”[4]
The law of excluded middle – a statement is either true, or its negation is true. There is no middle state between existing and not existing.

There are other tests for truth, but these are foundational prerequisites, for no matter how coherent or comforting a claim is, if it fails these tests, it simply can’t be true. And this is how “relative truth” fails.


[1] John 18:38, NASB.
[2] “Truth”, Webster’s Encyclopedic Unabridged Dictionary of the English Language,  1996 ed.
[3] J.P. Moreland & William Lane Craig, Philosophical Foundations for a Christian Worldview, (InterVarsity Press, 2003), p. 132. See also D.Q. McInerny, Being Logical, (Random House, 2005), p. 26-28.
[4] Avicenna, The Book of Healing, Part IV, Metaphysics I, commenting on Aristotle, Topics I.11.105a4–5, published 1027.

Lost Compasses

compass_smallMy latest bulletin from the Oklahoma Engineering Board had an article about engineering ethics and the following excerpt struck me.

It has taken generations for professional engineers and professional land surveyors to create the level of public trust that they have been afforded. Unfortunately, years of competent and ethical conduct can be destroyed very quickly by one unethical decision. One such serious breach of the public trust happened in Oklahoma just a few years ago.  A city’s Public Works department was racked with a bribery scandal involving one of its own professional engineers and other professional engineers in the private sector. After pleading guilty to the charges, the professional engineers were sentenced to jail time and assessed large fines.  Following disciplinary investigations and hearings, the Board revoked each of their PE licenses.  As a way of explanation for this unethical and illegal behavior, the attorney for one of the engineers told the court that his client had ‘lost his moral compass’. [emphasis mine]

I used compasses a lot in the Army. They’re nice tools. They’re also susceptible to error. I remember the Land Navigation course at Camp Williams, UT had one mountainside that was very iron-rich. Finding waypoints in that area was difficult because of the havoc magnetic materials wreak on compasses. You had to work off of known points and correct the heading your compass was telling you in those areas. Otherwise, you could truly go around in circles. You may get through most of the course trusting this handy little tool, but if you follow it when it clearly doesn’t match up with reality (i.e. I know that mountain is to my north, but my compass says it’s to my south…), then you are setting yourself up for failure, much like these unnamed engineers did. In fact, as I learned in the army, and as my cross-country flights for my pilot’s license later reminded me, compasses don’t match up exactly with reality to begin with. We say a compass points north, but a compass actually points to magnetic north, which generally does not line up with  true north. So as useful as a compass is for pointing you in roughly the right direction, precise navigation with one requires using a map that tells you the “declination angle”, or how much magnetic north and true north differ in your area. Where I lived, it was a 15.3° difference.

It really comes down to a matter of truth, whether that’s true north versus magnetic north when you’re physically lost, or truth versus error when morally lost. It can be said that something is true when it correlates with reality. If it is objectively true in this manner, then it is true regardless of our perceptions or rationalizations. Reality, then, is a known reference point that we can use to check  ourselves.  For instance, even if I’m red-green colorblind, there are tests one can do to verify that the color of light being reflected off of some grass is, in fact, green, thereby validating the statement that “the grass is green”.  But what of non-physical questions such as the ones that typically form ethical dilemmas? We need a known point of reference in those areas also to calibrate our “moral compasses” and correct them if needed.  What “known point”, – what benchmark – can straighten our meandering paths through ethical quagmires?

  • As our position changes, it should be unchanging for us to figure out how far off track we are (like a  “resection” in land nav).  If unchanging, this known point, or standard, would be applicable universally, i.e. multiple people could reference it to “fix”, or locate, their position on the map.  Likewise, a good ethical reference point should not be subjective. It should apply equally to all, from Mother Theresa to Adolf Hitler.
  •   A known point is also applicable without respect to time. You could likely figure out your location each year on vacation in Yosemite by looking for Half-Dome or El Capitan as those huge cliffs aren’t moving year to year. Using the snowplow on the side of the road as a reference point because it’s been in the same spot your entire week of vacation likely won’t help next year. Another example of this is how a homeowner’s property lines may be determined off a monument marker a surveyor set as a known point over 100 years prior. Likewise, a good ethical reference point should be just as valid whether it’s 2014, or 1914, or 2114.
  • A good known point is easily identifiable. Trying to shoot an accurate compass bearing to “the 15th tree down from the 3rd boulder over” when there’s a giant rock spire jutting from a barren mountainside a few hundred feet away is just silly. Use the obvious landmark. Likewise, a good ethical reference point should be obvious. For instance, if your ethical standard requires lengthy research on your part to agree that something as horrible as say, torturing babies for fun, is wrong, then I strongly suggest you find a better ethical “landmark”.

Is there a system of ethics that can provide us the known point we seek? A comparison of the several different and highly nuanced ethical systems and variations of each will have to wait for another day (and probably take several posts to even scratch the surface) but consider this: the combination of deontological and classic virtue ethics found in the Christian Bible provides an unmoving reference point in the character of God that applies equally to all people in all places and at all times. It explains the notion that some things really are inherently wrong (like torturing babies for fun) and are not “wrong for you but OK for me”.  It provides a readily identifiable reference for us in God’s holy character. “Is this activity I’m considering (i.e. bribery) in line with God’s character?” No? Then don’t do it! Done, compass calibrated. Move on down the road.