This is the original version of this essay, as originally mailed out by me some years ago. I recently went through it again, making minor corrections, and reposted it at my blag, so you might want to read it there instead of here. Also, you can post comments there.
There are a lot of things that annoy me. I like to talk about them, and write about them, and make people listen to me, because it makes me feel better when I'm done. Even if I end up annoying someone else in the process.
So the other day I was thinking, and of course I thought of one of these things that annoys me more than a lot of other things. This would be how a lot of people look at scientists and their works and what they say, and dismiss it all as "just a theory."
Before I go any further: Don't be unreasonable about it. I believe every word I write here, but that doesn't mean that, if you disagree with some or all of it, you can't be my friend. If you would like to have a serious discussion about it, email me or contact me some other way. Oh, and I'm not trying to put anyone down here; I realize other people have their own beliefs too. This isn't so much saying that they're wrong, as saying why I think I'm right.
I'm going to set out and try and convince you of several things. Firstly, many people's perceptions of science, scientists, and what they do and believe, are fundamentally flawed. Secondly, people are way too quick to dismiss what scientists say, partly because of this, and partly because of some other minor reasons. And finally, the way many people define terms like "theory" and "scientific law" and "fact" is not the same as when those terms are used by scientists, leading to much misunderstanding. After this I think I'll do some "case studies" and explain why I'm right and why everyone else is wrong (well, isn't that what you're supposed to do in papers? seriously though, if you have a logical disagreement, talk to the hand. lol, no seriously now, send me an email and we'll discuss it, just try and be a bit open-minded about it ok?)
I suppose the best way to start this is with an explanation for what I believe many people perceive science as. If I were to ask someone "What is science? can you point to something from science?" I believe many people are likely to talk about something like rocket ships or airplanes or test tubes and genetic manipulation. Scientists are perceived as inventors who make new things to use, and they do it for money or to make things easier for themselves and others, and they do this by trying things until the find something that works.
This is really not what scientists do; it's a lot closer to what engineers (like myself) do, and even then it's a very simplistic view of it (engineers still need to understand the basic scientific concepts behind things in order to invent stuff with them).
Science, in the broadest sense, is the search of knowledge. Knowledge of all kinds. This applies to virtually everything, which is why linguists and sociologists and political scientists can get away with calling themselves scientists. However, science is generally divided into two categories, for just this reason: Social Sciences (which includes things like history, linguistics, psychology, sociology, economics, political science, and anything else that has to do specifically with people and what they do), and Natural Sciences (which includes fields like chemistry, physics, geology, biology, and basically anything else that just is and doesn't depend on people). For simplicity, for the rest of this writing I will use the words "science," "scientist," and other words like that to refer just to the natural sciences (social scientists use terms slightly differently, so I'm just going to ignore them for now).
I'd like to make a further point of clarification here. I just defined science as the "search of knowledge." In contrast, many people believe that, in researching something, a scientist has a particular goal in mind, something that he or she (do you mind if I just use "he"? it's perfectly alright to do that in most other languages and I promise I'm not being sexist or anything when I do it) wants to have when they're done, usually some kind of device with lights and buttons that make it do things, or (for biological and genetic research) something like a new animal or other organism that does something neat. Again, this is the work of engineers; scientists do not have any end-use in mind when they are researching; they just want to know more about the universe and how it works. Eventually some of this knowledge can be found to be useful in everyday life, and engineers will put it to use. A good example is electricity. When Michael Faraday was presenting his research on this relatively newly discovered phenomenon to various important British people, the Chancellor of the Exchequer (something like a Minister of Finance) asked something amounting to, "what's the practical use of this research? What can we use it for that justifies our funding your research?" Faraday's response was simply "I do not know, but one day, sir, you may tax it." And indeed, most governments put some kind of tax or another on electricity, and as you know, by the 1900's many practical applications of electricity had been found, and to this day even more are being discovered. Note, however, that while research was going on as long as 150 years ago on this, we have yet to exhaust the possible technological applications, and it was indeed several decades before any were found in the first place. I would say that it was worth it, though (as would most of you, if you're reading this by email).
I hope that I've explained that well enough. If not, please send me a bug report and I'll fix it in version 1.1
Now that I've defined science I shall move on to defining a scientist. A scientist is a person who seeks after knowledge (as explained above) and follows what is called the scientific method in obtaining new knowledge. I'll explain that later, as it is very important.
For the last part of the first point I wanted to make, I must explain what scientists believe.
Scientists come from all kinds of backgrounds, every race, gender, economic circumstance, country, and (most important for this), scientists come from every major religion, and many minor religions, in the world. Most retain those beliefs throughout their career as scientists (it's not like there's some secret scientist ritual where they have to give up all beliefs in God or Gods and become flaming atheists or something, even if that'd make for a pretty cool theme for a movie or something...just imagine..."One rogue scientist, who must bring down the Institute, in order to save his God"...ok I'm a bit ridiculous sometimes, that's why this is in parentheses). Science does not require that you believe anything on faith, so it in no way competes with religion. Seriously. A lot of what science tries to find out are what is, and so far it hasn't been able to go very far as to why things are, which leave plenty of room for religious beliefs. There are some places where claims made by religion and claims made by science overlap. At the risk of getting some of you mad at me, I'm going to go ahead and say that this is usually because the religious claim is usually something that is physically impossible, or better: that it is impossible for the scientific claim to be wrong. I will explain later, I promise.
So as for religious beliefs, you cannot say that there is any one label you can pin on scientists as a group (well you could, but you'd be wrong 8-) ). What scientists do collectively believe is that they can research things, and acquire new knowledge, and that everything that they learn must be proved beyond a shadow of a doubt, before it can claimed to be true, and knowledge which has thus been proved must be true, unless new evidence surfaces causing its premises to be proved untrue (there have been cases of this which I shall explain in my case studies; by the time I'm done though you'd better know more about chemistry than you did when I started).
I believe that by now I have explained enough of what I meant about "science, scientists, and what they believe." As far as I can tell I have answered any questions that could arise about this, and I feel ready to move onto my next point.
Scientists study things all the time, but it takes a lot of data before they are willing to generalize their findings and publish a paper with their findings (well, in some cases people pressure themselves or others into doing it too fast, but when this happens and incorrect assumptions are made, they are caught further down the line). When they do publish on a new principle or idea, it is because the are sure it is true, or believe that they have uncovered a new idea which can be studied by others who can help prove or disprove something (and they state clearly which of these it is).
In order to prove a new discovery, scientists use the Scientific Method: an exhaustive approach which is meant to find patterns behind data, and provide new explanations and scientific laws and theories, and also give a framework for proving them. Everyone who's gone through high school should know it, but I will outline its basic steps again:
Observation
The first step in the scientific method is to make an observation on something. Often it's something that happens. As an example, an observation made by a physicist might be "birds fly and bricks don't."
Hypothesis
The observation made in the first step can be taken a step further by asking why or how something happens, or why or how it exists, why or how it exists where it is or how it is, or something along those lines. For example: "Birds might fly because they have wings; bricks might not fly because they don't have wings." This statement is called a "hypothesis" and is what many people (incorrectly) refer to as a theory; it is an "educated guess" that attempts to explain the state of things, why things exist why they do. An important feature of most hypothesis is that they are testable by experimentation. (other hypothesis might be "birds fly because of their shape" or "birds fly because they are alive and bricks don't because they aren't" or "birds fly because they weigh less; bricks don't since they weigh more" or "some combination of all of these").
Experiment
After a hypothesis is formed, it must be tested by experimentation in order to prove whether it is true or not. Initial experiments must be performed under careful conditions; everything about the tests must be identical for everything being tested, except for one factor (called the "independent variable") which is adjusted. For our example, you would take two bricks with identical weights, put wings on one of them, and drop them both at the same time, from the same place, and see whether either one flies (neither one probably will, but in later tests you would do things such as adjusting the size of the wings, adjusting the weight and shape of the bricks, and other similar things, to find that you need the right set of wings for the right brick, and only under these conditions can you make a brick fly) (you could also do this by taking one bird with wings and another without, but that would be cruel, and scientists have feelings too, so most of them wouldn't do this. With birds that are still alive, at least).
Experiments are repeated many times, varying all conditions, and with all conditions being specifically recorded. If some condition which might affect the results (whether it's windy, what the barometric pressure is, how far up you're dropping the bricks from) is not recorded, then all the data has to be thrown out. No question about it.
Conclusions
After many experiments have been conducted, scientist can take the data and do fancy things with it, like putting it in an Excel spreadsheet and make charts. This can be helpful to determine whether our hypothesis was correct or not, and from this data they basically conclude whether their hypothesis was totally incorrect, totally correct, or just part of the explanation (as would be the case with our hypothesis that whether bricks could fly depended only on whether or not they possessed wings). This conclusion can be published. If the hypothesis was found not be a total, complete explanation for what you were investigating in the first place, accounting for every circumstance possible, then the conclusions must be used as observations to form a new hypothesis (such as "whether or not a brick flies depends on weight as well as whether or not it has wings") which is then tested.
This method may kind of look a bit haphazard, since it starts with basically a guess, but it really isn't. If that "guess" proves to be untrue, then it is discarded and replaced with another "guess" which is also tested. This keeps going until one of the guesses appears to be true; it is then tested under every possible circumstance, and as soon as one set of circumstances proves it to be untrue, the guess is discarded, or modified to suit the new information. Since information about all of these experiments is shared between scientists, massive amounts of data accumulate for each problem, and after enough time has passed, there is enough information to say that something is always true, or always false, or something like that. Only at this point, however, is something accepted as anything more than a hypothesis.
Therefore, when a scientist says that something has been proven true, that means that it has been tested by a variety of people under every possible condition, and has always withstood testing. Always. That means it hasn't failed even once. And if it does fail once, then it is no longer true; it might be said to be "usually true" or "generally true" and most of the time it's still good enough for most people to go by, but it isn't a scientific fact.
That last part might not have explained it well enough, but my point remains that, when science proves something, that means it's true. No questions. If you try to get a spaceship up to the speed of light, it's not like Einstein is going to pull you over and give you a ticket for breaking the universal speed limit; you just can't do it. That means it's not possible (even though I'd pay a ridiculous amount of money to get my spaceship pulled over like that. I mean, how cool would that be?). So when a scientist says something's true, it is. Not because they say it, but because they mean it (yes, scientists are human, and they can lie, but that's why you should look things up yourself too).
Now it's time for some terminology to clarify what exactly scientists mean when they say things.
First of all, the "classical" view of what an experiment is is something like this: A scientist walks into a lab, grabs a test tube, pours two chemicals in together, and finds out what happens. Now after knowing the scientific method you should know that this does not happen like that; experimentation is done only after a hypothesis has been made, and it's done in a very careful, controlled manner, so as to get meaningful and usable results.
Secondly, what is a hypothesis? Once again I kind of told you above, but for clarity: what most people call a "theory" is referred to by scientists as a hypothesis; an educated guess at an explanation for why something happens, which can be tested and proved or disproved.
Another term is fact. In science, a fact is something that is. No explanation or anything, it just is (for example, if you're doing the experiment we talked about with the flying bricks, you know that the brick exists. That is an example of a fact).
The last two terms are the most often-confused ones, and require the most attention. I shall start with a law.
A scientific law is a generalized description (usually with some sort of relatively simple equation) of a physical phenomenon which always holds true under conditions defined in the law. Many times people look at some examples and say "this isn't exactly true" but they are forgetting some conditions of the law. For example: For an ideal gas (that is, a gas whose particles/molecules/atoms are small enough in comparison to the container that you can ignore that they exist, and whose particles/molecules/atoms have absolutely no interaction), held at constant pressure and constant amount of gas, the volume of the gas is proportional to the temperature of the gas. This means, if you bring the gas to a low enough temperature (turns out this temp is absolute 0), the gas has no volume. You know that it's not possible to do this, but that's because there's no such thing as an ideal gas; at least, not when it gets that cold (helium acts like an ideal gas under most conditions). Another example is Newton's First Law of Motion, which is generally paraphrased to "An object in motion tends to stay in motion; an object at rest tends to stay at rest." You could point out how friction slows things down; but you would be ignoring the first part of Newton's Law, which states: "If no external force is applied on the object...." (friction is an external force, so is air resistance, gravity, and other stuff like that).
Scientific laws can also be called (according to my chem teacher this semester) "Summaries of tested hypotheses proven experimentally, with absolutely no exceptions." Many things predicted by scientific laws can not actually happen, because it is impossible to have absolutely no external forces, or an absolutely ideal gas, but the laws still help to understand the principles behind what's going on; other things (such as interactions in gas or friction on moving things) just add more stuff to the law later.
A scientific theory is an explanation of some natural phenomenon. Another way of putting it: a theory explains a law based on fundamental, proven concepts. Usually, a scientific law describing what happens is discovered many years before an acceptable theory is formed to account why things happen that way.
Theories are also based on experimental evidence, and can be considered to be as true as the scientific laws they explain, for similar reasons: as soon as a phenomenon is found that does not fit a scientific law, then the law is no longer a law; it is a rule, or equation, which is said to "generally" work, but is noted to "have exceptions." These are still useful, especially to engineers, but scientifically they are no longer absolutes.
Theories can be "disproven" too, if a phenomenon does not fit the explanation put forth by the theory. Disproven theories can still be useful too, but not nearly so much as disproven laws which are "rules" or "equations."
Some may ask, "if you're so sure it's true, why is it a scientific theory and not a scientific law?" Well I think I just answered that above; a scientific law describes what happens and is used to predict what will happen under varying conditions; a scientific theory explains why it happens, and can be used for a deeper understanding of how things work. Theories do not become laws, because they deal with different things.
But what I'm trying to stress is, a theory isn't just a theory. A theory fits everything that we know about the universe, and provides an acceptable and usable explanation of how the universe works, in terms of basic concepts and facts that are known to be true.
Now this should be an acceptable explanation for you, so I shall go on to do a couple examples.
At one point in time, people believed that gas was nothing, that the air we breathe was as empty as outer space (actually more so). Since you can't see gas, it must not have particles. However, as the science of chemistry was growing from its infancy, several interesting phenomena were noted. No matter how good of a pump someone made, they could not pump water any higher than 34 feet. When a column of mercury was inverted, a hollow space would form at the top, but the tube wouldn't empty all the way; it would run partway out and then stop. When a container was heated up, a pressure would build up inside.
Scientists like Boyle distilled some of these concepts into scientific laws (under constant temperature and amount of gas, the pressure and volume of a gas are inversely proportional; Charles' law states that, at constant pressures and amounts of gas, volume and temperature were proportional; Gay-Lusac found that pressure and temperature were proportional at constant temp and amount, and Avogadro found that at constant pressure and temperature, volume and amount of gas were proportional). This led them to wonder; how can something that is nothing exert pressure? The answer was, of course, that it wasn't nothing; and led to the formulation of the kinetic theory of gases (gases are made up of many very tiny particles which are constantly in motion).
These laws don't hold up under very high pressures or extremes of temperature, but that's because, under high pressures, the actual sizes of the gas particles/atoms/molecules start getting in the way, which violates the premise that the gas particles have negligible volume. So this theory is used today, and has not been (and in my opinion will not soon be) changed.
Let's expand on this a bit more. Those laws stated above are summed up in what's called the ideal gas law, which is generally given as PV=nRT, where P is pressure, V is volume, n is the amount of gas, and T is temperature, and R is a constant of proportionality whose value depends on the units of P, V, n, and T. The reason it is called an "Ideal Gas Law" is because it works for "ideal gases;" gases whose particles are so small in comparison to the container they're in that you can ignore them, and which do not interact at all with each other. Under most conditions, this law describes the behavior of real gases pretty well (a real gas has particles which interact with each other to varying degrees depending on chemical properties, and which have a real mass which at normal temperatures and pressures is negligible but becomes a problem at high pressures). The fact that it doesn't hold up all the time for real gases doesn't disprove it, since the law states that it is a law for "ideal gases" (see how that works? It might seem like cheating to do that, but it isn't, because it is impossible with today's technology to do the calculations required to determine exact equations for real gases).
Another case: molecular theory. The theory of electrons and orbitals and such has long been a problem. Originally it was not understood very well, and just said that it had something to do with the atomic orbitals of the atoms involved. Later, something called valence bond theory stated that electrons in the valence shells of atoms could be shared by atoms to form chemical bonds. Orbital hybridization theory explained how atomic orbitals could be rearranged to explain the geometry found in real atoms, and molecular orbital theory explained how atomic orbitals could be combined to share electrons and form molecular orbitals. The latest explanation, which accounts for some things in the geometry found in real molecules, is the Valence Shell Electron Pair Repulsion theory, which holds up to everything we know about atoms and electrons (atoms can rearrange their orbitals to share electrons, and since electrons share the same charge they repel each other, and they generally form groups of two in any given orbital for reasons I don't care to explain). (If you're more lost after this explanation, it's ok, you haven't got to it yet).
Christopher Columbus is often credited with being the first person to believe that the world was round. This idea is incorrect in the first place (Aristotle and a couple other Greeks believed this, and actually proved it, with a very good estimation of the actual diameter of the earth); in fact he was not even the main believer of it at his time (most educated Europeans in the fifteenth century knew of this; Columbus just believed the world was a lot smaller than it actually is). What place does this have here? Well, Columbus didn't have a theory, and he wasn't a scientist, and it's another thing that is often misunderstood.
A very good example of people reacting badly to scientific theories was that of Galileo Galilei, the Italian astronomer who was one of the first who hypothesized that the universe might not center around the earth (http://en.wikipedia.org/wiki/Galileo_Galilei). What he observed was this: The planed Venus appeared to reflect light from the sun. In addition, from the Earth's perspective, Venus appeared to sometimes disappear behind the sun, and other times to be in front of it. At the time, the scientific establishment and the Church accepted that the Earth was the center of the universe and everything revolved around us. He observed all of the planetary bodies in the solar system that could be found at the time, and they all fit this hypothesis. His views got him in trouble with the academic establishment, his sponsors, and (worst of all in the times of the Inquisition) with the Church. In 1616 he went to Rome to plead his case...and lost. He was told not to tell of a sun-centered solar system as fact...or else. He talked about it as a "what if..." for a while, but in 1632, at the assumption of the next pope, he resumed. However, upon publishing his book, he was later brought to Rome to defend his ideas and called a heretic. He was required to take back his theory and placed under house arrest, and worst of all (or at least to me, probably not to him but idk), his book was banned. He was allowed to move once, but lived for the rest of his life under house arrest because of his observations. Fortunately for us, we know now that he wasn't just making it all up. Over the years the bans on his books were gradually lifted, and in the year 1992 (well within my lifetime) the Pope "expressed regret for how the Galileo affair was handled, and officially conceded that the Earth was not stationary, as the result of a study conducted by the Pontifical Council for Culture" (Wikipedia).
As my final example I'd like to bring to light another, slightly more recent scientist, who proved something which was found disagreeable, and which is still a matter for debate to this day, despite the amount of evidence on his side.
Charles Darwin is one of the most maligned scientists to ever live. At the time he published his findings, he had put off publishing for decades already for fear of the uproar it would create; and he in fact underestimated what truly happened. People believed he was calling into question their fundamental beliefs; they ridiculed him, parodied his theory, and all kinds of things. This was not for his lack of proof; he had gathered sufficient evidence to back his theory (which, I might add, has yet to be disproven) of how species change over time (which previously had been claimed to not happen, even though new breeds of dogs had been developed within the decade). Nor for a lack of independent corroborating evidence; the event that got him to publish his paper when he did was a letter from Charles Wallace, a naturalist studying species in Australia, which contained a theory exactly the same as Darwin's own (Darwin published right away because he had been organizing information for years, and didn't want Wallace to get credit first, which is actually fair since Darwin's work was done first too).
Today, Charles Darwin's theory of evolution is widely accepted by the scientific community, especially with all the evidence that continues to accumulate in its favor, but certain groups view it with something less than enthusiasm. They claim it is "just a theory" and that it should be given equal time with other explanations (explanations which I don't find entirely incompatible, but many of which are not at all scientific). I wish people would get over it. Species change over time in response to changes in their environment, through natural and sexual selection (no that's not a dirty word, it just means every guy wants the hottest girl and every girl wants the hottest guy, it's true for all species). And Charles Darwin never said "humans evolved from monkeys;" what he suggested (and, what modern genetic research has agreed with) is that, some point in the distant past, humans and apes branched off from a common ancestral species, which was neither human nor ape.
When he set out into the world, Darwin was not intending to cause the uproar he did; he merely intended to observe the world around him and see if he could make any inferences from it. Well, that's what he did I guess, but unfortunately it led to an uproar, which continues today. It really makes me kind of sad.
I have stated my case, now it's up to you. But just remember what I've told you the next time you, or anyone else you hear, says "It's just a theory."
Nick Leep
ps picture is from http://xkcd.com/54/
