Last week’s procession of trick or treaters and campaigning politicians, ringing our doorbells, seeking candy or votes, made me more determined than ever to continue our discussion concerning critical thinking. I can’t think of a better time than the period between Halloween and Election Day to consider such compelling topics as time travel, extra sensory perception, telekinesis, Ghosts and, of course, politics. I invite you to join me on an intellectual journey as we search for the truth behind these interesting and hotly debated topics. To begin, we must choose the tools, which are essential, if we are to make any progress at all.
First, we must dispense with an age old detour in any quest for knowledge, comforting personal preferences. In our daily lives, we often hear people express their “beliefs” without supplying an iota of evidence as to why their particular conviction is true. Of course, everyone is free to believe whatever he or she chooses. However, for our purposes, “belief” without any significant supporting evidence will not bring us an inch closer to the truth. Similarly, a hasty acceptance or rejection of a claim provides us with no help in assessing its veracity. Beliefs that are not based on reason and evidence signify nothing, except our feelings and personal preferences.
Philosopher, Brooks Atkinson, put it this way, “People everywhere enjoy believing things that they know are not true. It spares them the ordeal of thinking for themselves and taking responsibility for what they know.” In our quest for truth, we must move beyond wishful thinking to critical thinking. This requires that we set aside prejudices and preconceptions, in order to examine the evidence fairly and impartially. By so doing, we are able to distinguish reality from fantasy and truth from lies. Our process ultimately encompasses three considerations: possibility, plausibility and reality. Our starting point today is an examination of “possibility.”
Every system of belief, rational or irrational, inevitably begins with the premise that something— logic, God or the Universe—is simply a “brute fact.” The exercise of critical thinking is no exception. Known as Aristotle’s “law of identity,” our brute fact will be “the law of non contradiction”. Simply stated, it means that nothing can both have a property and lack it at the same time. Flowing naturally from this principle is what is called the law of identity, or that everything is identical to itself. Without these principles, we can’t know things to be one way rather than another. If that were true, all thinking would be impossible. These basic axioms teach us that the slogan, “everything is possible,” is untrue. Things can be logically, physically or technologically impossible.
Logical impossibility occurs when the concept considered contradicts itself. We know, for example, that there cannot be a round square, a married bachelor, and so on and so forth. Precognition also falls into this category. We can only perceive what currently exists. If someone can perceive the future, it implies that the future presently exists, which by definition is untrue. So precognition commits us to a logical impossibility; hence, it must be considered false.
Similarly, time travel is logically impossible because it implies that an event both did and did not happen. Let’s say you travel back in time to a place you’ve never been. History has already recorded that you were not present at that place and time, but now you are. You cannot both be and not be at a place and time. Time travel violates the principle of non-contradiction. If you look carefully at successful science fiction writers, their “time travelers” go to parallel universes rather than their own.
Physical impossibility says that anything inconsistent with the laws of nature is impossible. So the expression “when pigs fly” does in fact refer to an impossibility because flying pigs would violate the laws governing pigs, physiology and gravity. Pigs don’t have wings and even if they did, their massive weight would prevent them from escaping the earth’s gravity. Physical impossibility is a more limited notion than logical impossibility. Whatever is physically impossible is usually logically possible, but not everything that is logically possible is physically possible.
Telekinesis, the ability to move external objects with the power of one’s mind, is physically impossible because it requires the existence of an unknown force. There are only two known forces in the universe, electromagnetism and gravity. The brain is not capable of producing enough of either of these to directly affect objects outside the body. Telekinesis, therefore, cannot be true since it violates the laws of nature.
Technological impossibility is the only “impossibility’ that displays even a modicum of flexibility. Something is technologically impossible if it is currently beyond our capabilities to accomplish. Manned inter-galactic space travel is impossible because we do not have the wherewithal to store enough food and energy to travel to another galaxy. It’s not that it’s logically impossible or that we are breaking any natural laws. We simply lack the technology to perform the feat.
The makers of the movie, Interstellar, understood that travel among the galaxies, the entire premise of the movie, is technologically impossible. Given the present state of our technology, it would take 5000 years to reach the closest solar system possibly suitable for human life and 13,000 to reach the second most habitable system. To remedy this problem, the filmmakers envisioned three futuristic forms of advanced energy: Thermonuclear Fusion, Laser Beam and Light Sail, and Gravitational Slingshots in a Black Hole Binary. As exciting as these concepts are, they do not exist either today or in the near future. Using today’s technology, we are prohibited for thousands of years from reaching other solar systems.
The first stage of critical thinking (possibility) as well as the two we have not yet discussed (plausibility and reality), are not just useful when we are examining supernatural phenomena, but are indispensable when accessing the various claims and promises made by those who seek our votes. When properly applied (as we shall discuss in future columns) these tools will not only help us survive the scariest ghost stories but also facilitate better and more informed decisions come this and every Election Day. In the meantime, I wish you a belated Happy Halloween!