An Intentionally Untechnical Essay

No way of thinking or doing, however ancient, can be trusted without proof.

---Henry David Thoreau

Sometimes, as scientists and philosophers, we tend to become a bit pedantic in our use of certain words, especially those we are particularly fond of. One of those words is proof.

Ever since the philosophies of Hume and Kant undermined the foundations of knowledge, there has been a steady disintegration of confidence in all sources of knowledge, but especially in the sciences. It is not at all uncommon today to hear scientists say things like, "nothing is ever really proved in science," or "science is not really concerned with proof."

It is true that proof is not the main purpose of science. The main purpose is discovery. Proof is not part of science until scientists believe they have discovered something, like a new phenomenon or an explanation for something. The purpose of proof is to determine if a proposed discovery really is what it is presumed to be.

Since critics of science, and many scientists as well, have taken this dim view of proof, the whole field of science has suffered. One result has been a proliferation of pseudo-scientific claims, which, so long as "proof" is not required, receive just as much respect as legitimate science. The other result is that legitimate science and scientists have lost one of the guiding principles of science.

The most damaging result of the repudiation of proof, is a prevailing and general opinion that there is really no proof of anything. It is one of the dominant symptoms of the anti-intellecual spirit of our age.

What is Proof?

Everyone uses the word proof from time to time and in most cases everyone knows exactly what they mean.

When my wife asks, "Honey, did you leave the keys in the car?"
And I answer, "I'm sure I didn't. I always take them out of the ignition when I get out of the car."
The proof comes when, in a little while I hear, "Honey, I found the keys."
"Oh really. Where?" I ask, cautiously.
"In the car," she says, nonchalantly.

My wife had a theory1 my keys were in the car; I had a theory they were someplace else; when my wife found the keys in the car that was proof her theory was correct and my theory was wrong.

This illustrates what proof means in everyday language. All other supposed meanings are either refinements of this everyday meaning, or esoteric meanings pertaining to special cases.

Since this is only an illustration, we should define the everyday meaning of proof as follows:

Proof: Something which demonstrates what we suppose is the case is actually the case, and therefore, true.2

"Something which demonstrates," can be anything so long as it accomplishes the task of demonstrating the supposition or proposition is actually true. It could be a logical argument, an experiment, or simply presenting a specimen of a fact, for example.

"What is supposed is true," is any proposition, usually in the form of a statement or series of statements, that asserts something (a quality, characteristic, a relationship, or existence itself, for example) about something else (an entity, event, concept, or relationship, for example).

"Actually the case" or "true" means that what is asserted is exactly as it is asserted to be.

My wife's hypothesis asserted a specific relationship (in the car) about an entity (my car keys) which she demonstrated (by looking and finding them in there) was actually true. That is proof, at least in everyday language. Proof, in this sense at least, in not only possible, but we do it all the time. Whether there is any other kind of proof remains to be seen.

What About Serious Proof?

The car keys example might seem like a trivial example, but it is exactly what proof is. Understandably, most people will brush an example like this aside to ask, "but the issues in science are both more complex and more universal, can we really prove anything in science?" The sad thing is, this question is meant seriously.

The answer is, of course we can prove things in science, and we can prove them conclusively, and have done just that, not a few times, but many times. The fact this is not obvious to anyone living in present day America demonstrates just how successful the anti-knowledge anti-intellectual, anti-human movement has been.

For those in the movement (most of academia, for example), and those who have been completely swayed by the movement (most of those educated in today's colleges and universities), nothing is going to change their view that "absolute proof" and "certain knowledge," are impossible.

Speaking for themselves, they may be correct, but, for the rest of us, as a reminder of what the human mind is capable of achieving, especially when it is free to achieve, consider these well-known proven truths.

Aristotle and Galileo

It is difficult to admit faults about one's friends but even harder to admit them about one's heros. In the field of philosophy, Aristotle is one of my heroes, but in the field of science, I'm afraid Aristotle was a great failure, and we know the cause of that failure. He used the wrong method.

Aristotle thought he could use in science the same method he used in philosophy. Philosophy deals primarily with ideas and the method for dealing with ideas is mostly thought. Science deals with the observable material world, to study that, one must observe it and perform experiments so one can observe it as carefully and completely as possible.

Bertrand Russel points out Aristotle might have avoided one of his many scientific mistakes by the simple experiment of asking Mrs. Aristotle to open her mouth and observing, by counting, how many teeth she had. Instead, he only thought about, and concluded women had fewer teeth than men.

Fortunately for science and for mankind, Galileo, using the correct method, was able to correct at least two of Aristotle's really big scientific mistakes.

Aristotle thought "heavy objects fall more rapidly than light objects."
Galileo demonstrated "all objects fall at the same rate."

Aristotle thought "Objects remain in motion only so long as a force is continually exerted to propel them."
Galileo demonstrated "Objects in motion remain in motion until some force, like friction, slows or stops them."

Science Verses Scientists

Not only philosophers but scientists as well, are frequently infected with the idea that true science can be carried out merely by thinking and without actually observing. For such scientists, even demonstration is not proof.

In 1902, Rear-Admiral George Melville, chief engineer of the US Navy, wrote in the North American Review, that attempting to fly was 'absurd'. In 1903, Simon Newcomb, professor of mathematics and astronomy at Johns Hopkins University published an article which showed scientifically that powered human flight was 'utterly impossible,' and would require the discovery of a new force in nature. A few weeks later, Wilbur and Orville Wright did the scientifically impossible.

For five years after the Wright brother's first successful flight, most American scientists, science editors, and science writers in the NewYork Herald, the North American Review, and the Scientific American dismissed the many demonstrations of powered human flight as a hoax.

In 1908, President Theodore Roosevelt ordered public trials at Fort Myers, which finally convinced the scientists, the Army, and the press that powered human flight was possible after all. The Wright brothers had proved it, five years earlier.

Aristotle Vindicated

Aristotle may have been a failure at science, but it was because he did not follow the principles of his own philosophy. Hundreds of years later, others would follow those principles, transforming science for all time from a mystic adherence to superstition and authority, into a truly objective science.

Between the end of the sixteenth century and the the early part of the seventeenth century, in defiance of the traditionalists and Galenists of his time, an Aristotelian named William Harvey3, theorized and confirmed blood pumped out from heart, returns to heart. Although his discoveries were still debated by authorities and scientists after his death, he is today considered the founder of modern physiology, and every fifth-grade student takes for granted this fact proved so long ago.

From the World of Fiction

In Mary Shelley's 1818 Gothic novel Frankenstein, the monster was "brought to life," with an electric shock. That it might actually be possible to revive a dead person with electricity, especially one made out of, "spare parts," so-to-speak, is, of course, nothing but wild speculative fiction.

But, today, there are more than a few people walking around with, "spare parts," taken from dead people, and when that spare part happens to be a heart, it was restarted with an electric shock.

Electric shock, called cardioversion or defibrillation, is used all the time to revive people whose hearts have stopped, and are technically dead.

Can it be proved people can be brought back to life by electricity? Try telling anyone who is alive because they have had a heart transplant or have had their heart restarted by electric shock that no one can prove it.

Stationary at 6000 Miles Per Hour

Another fiction writer, Arthur C. Clark. wrote an article in 1945 stating that communications signals could be transmitted to and from Earth by a relay station launched into orbit around the earth's equator at a distance of about 22,300 miles. At that altitude, the "satellite" would maintain a stationary position over the earth, by maintaining an orbital speed of approximately 6000 miles per hour.

Of course this was mere speculation, and by a science fiction writer, of all things. It could not be proved, of course, at least not for a few more years.

Proof is Ubiquitous

It is almost impossible to believe anyone could doubt that proof is not only possible, but one of the most common things in the world. Almost everything about modern life is proof of some scientific or mathematical hypothesis or discovery.

Every electronic device or machine we use which is powered by electricity from the power grid, as well as, the power grid itself is proof Michael Faraday was not the charlatan his contemporaries accused him of being when he announced he could generate an electric current simply by moving a magnet in a coil of wire.

Every time we listen to the radio or watch television we prove once again that wireless communication is possible, despite the resistance Nikola Tesla, Guglielmo Marconi, and others faced when first promoting it.

If you ever have to have surgery, you can be thankful the horrors that always tormented patients with pain so excruciating it frequently killed them or left them insane is no longer true, because it has been proved, painless surgery is possible.

But Can You Prove there is Proof?

No, no one can prove it to anyone who would ask that question. When someone asks this kind of question, what they really mean is, "can you convince me there is proof." That kind of proof does not exist.4

The purpose of proof is not to convince others, but to ensure that one's own reasoning and conclusions are correct. If proof depended on convincing others, the few examples we have provided demonstrate almost nothing would ever have been proved.

The Wright brothers proved the possibility of powered human flight almost five years before they could convince anyone else it had been proved. Robert Goddard5, whose experiments proved the principles of gyroscopically controlled rocketry he said would one day take men to the moon, was all but ignored, except by the Germans who used the principles to design V2 rockets. Most people were not convinced until men had actually walked on the moon some 30 years later.

The reluctance to accept the claims of just anyone about a new invention or discovered principle of nature, especially without proof or enough evidence to warrant further investigation is a good thing. This kind of resistance to new claims is sound skepticism. What is not sound skepticism, is rejecting a thing without examining the evidence or without even knowing what the argument is. This false skepticism is an assertion that something is true (that what is being rejected is false) without proof or evidence. It is another variety of, "well nothing can be proved anyway."

The Price of Infamy

How did the idea of proof ever fall into such disrepute that even very many serious and intelligent people doubt it? We are not now concerned so much with those whose agenda it is to attack anything that smacks of real objective knowledge, though many have no doubt been influenced by that camp, which manifests itself in all aspects of what is nowadays described as post-modernism, but most obviously as, "multiculturalism," "political correctness," and "diversity."

The word "proof" itself no doubt lost much of its reputation, soon after the enlightenment, when the first striking examples of what scientific proof was capable of manifested themselves. This was a very powerful concept. Once a thing was proven, and everyone knew it, it swept away everything that opposed it, and changed everything touched by it, not by force, but by light.

The word "proof" immediately became the favorite of con men and charlatans promoting their scams, cures, and useless devices. It remains to this day, the most common word used in the hawking of alternative medicine and all other quackery. It is understandable that people became suspicious of this word. Certainly nothing should be accepted or believed just because the claim of proof is made for it. This does not mean the word proof itself ought to be rejected, because its real meaning is both legitimate and important.6

The other "honest" reasons for a hesitancy to embrace the concept of proof are mostly a matter of misunderstanding about its true nature:

  • We cannot know everything - The idea that we most know everything to know anything is frequently implied by those who deny anything can be proved. When made explicit, we see there is no basis for this view. We do not have to know everything, to know something.

  • We are not infallible - Similar to the we cannot know everything objection to proof, it is almost never explicit. Again making it explicit makes the mistake obvious. The fact we can make mistakes does not mean that we can only make mistakes.

  • Proof is seldom neat - There is a common idea that proof must follow some preconceived notion of regularity and formality, like a rigid three or four step process. In fact, proof often comes in a very disorderly fashion, like two bicycle repairmen in a clumsy contraption that just barely performs the thing they are trying to prove. Proof is proof, however, no matter how clumsy or inelegant it is.

  • Some things are difficult or impossible to know - This is true. So what? Many objections to proof dwell on things which are truly difficult, maybe even impossible to prove. Proof pertains to those things that can and have been proved.

  • When looking at the trees through the window, we do not see the window - The very odd thing about proof is its very commonplace nature. We are tempted to wonder if those who deny it have just arrived from another planet or been asleep all their lives.

    In fact the attitude, from this aspect, is really understandable. Our lives are saturated with proof and the proven, but most have become so commonplace, we just do not notice them. We are oblivious to the almost superhuman intellectual effort required to wrestle these truths from obscurity and ignorance and force them into the light of knowledge.

    Every child today knows and understands things we are all so familiar with, they seem obvious, but those same concepts, just a few hundred years ago, were inconceivable and unfathomable. The only reason they seem obvious to us is because they have been so conclusively proven that no one can imagine doubting them, or that they ever needed to be proved.

---Reginald Firehammer


1. What she really had, of course, was a hypothesis, and it did not become a theory until it was proven to be correct. My hypothesis, on the other hand became a hypothesis proven incorrect.

2. Here is a dictionary definition of the word proof:

(The American Heritage® Dictionary of the English Language: Fourth Edition. 2000)

NOUN: 1. The evidence or argument that compels the mind to accept an assertion as true. 2a. The validation of a proposition by application of specified rules, as of induction or deduction, to assumptions, axioms, and sequentially derived conclusions. b. A statement or argument used in such a validation. 3a. Convincing or persuasive demonstration: was asked for proof of his identity; an employment history that was proof of her dependability. b. The state of being convinced or persuaded by consideration of evidence. 4. Determination of the quality of something by testing; trial: put one's beliefs to the proof. 5. Law The result or effect of evidence; the establishment or denial of a fact by evidence. 6. The alcoholic strength of a liquor, expressed by a number that is twice the percentage by volume of alcohol present. 7. Printing a. A trial sheet of printed material that is made to be checked and corrected. Also called proof sheet. b. A trial impression of a plate, stone, or block taken at any of various stages in engraving. 8a. A trial photographic print. b. Any of a limited number of newly minted coins or medals struck as specimens and for collectors from a new die on a polished planchet. 9. Archaic Proven impenetrability: “I was clothed in Armor of proof” (John Bunyan).
ADJECTIVE: 1. Fully or successfully resistant; impervious. Often used in combination: waterproof watches; a fireproof cellar door. 2. Of standard alcoholic strength. 3. Used in proving or making corrections.
VERB: Inflected forms: proofed, proof·ing, proofs
TRANSITIVE VERB: 1. Printing a. To make a trial impression of (printed or engraved matter). b. To proofread (copy). 2a. To activate (dormant dry yeast) by adding water. b. To work (dough) into proper lightness. 3. To treat so as to make resistant: proof a fabric against shrinkage.
INTRANSITIVE VERB: 1. Printing To proofread. 2. To become properly light for cooking: The batter proofed overnight.
ETYMOLOGY: Middle English prove, preve, from Anglo-Norman prove and from Old French prueve, both from Late Latin proba, from Latin probre, to prove.

3. English physician William Harvey, April. 1, 1578 - June 3, 1657. 4. One problem with the notion that others must be convinced before something can be truly considered proved is the fact that many things which have been proved are too difficult for many others to even understand, much less be convinced about. How would one go about convincing the average person who has difficulty with basic arithmetic that the principles of the calculus are correct? 5. Robert Hutchins Goddard (1882-1945).

The first manned lunar landing was Apollo 11, July 16-24, 1969 (Neil A. Armstrong, Michael Collins, Edwin E. Aldrin, Jr)

6. If we are going to throw away every word that is misappropriated our entire language will be reduced to a handful of prepositions, conjunctions, and expletives, since there is hardly a noun, verb, adjective, or adverb that people do not misuse and abuse. How in the world do you explain to a child today what the gay '90s were or what a phobia is when anything anybody is opposed to on any grounds is called one.