Chapter 0: Science and Clear Thinking


"What gets us into trouble is not what we don't know. It's what we know for sure that just ain't so" - Josh Billings, (but widely attributed to Mark Twain - which just ain't so )


"Science is simply common sense at its best, that is, rigidly accurate in observation, and merciless to fallacy in logic" - Thomas Huxley

The Bennett et al. text "Cosmic Perspective" covers some of the standard material on the nature of science and scientific thinking, but I have some deeper thoughts on this and the larger role of scientific thinking in the discovery and evaluation of knowledge. Many of you will not have another science course. So I've put together this exposition on the subject of clear thinking in general and scientific method in particular. I don't know any scientists who would disagree with the thoughts on scientific thinking given here, although of course there might yet be a few. A first rate book for the intelligent layman on the nature of science, thought, and New-Age mysticism is "The Demon Haunted World" by Carl Sagan (free .pdf linked). Columbia University has developed an undergraduate program "Frontiers of Science" which is explicitly designed to show undergrad's how to "think like a scientist". Science is not a collection of nerdy factoids. Science is a way of thinking, not just about complicated physics'y things, but about everything in our daily lives. Ideally, we are all scientists in the way we gate-keep what knowledge we allow into our minds...

“Don't you believe in flying saucers, they ask me? Don't you believe in telepathy? In ancient astronauts? In the Bermuda Triangle? In life after death?" "No", I reply. "No, no, no, no, and again no". One person recently, goaded into desperation by the litany of unrelieved negation, burst out "Don't you believe in anything?” "Yes", I said. "I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I'll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be.” Isaac Asimov (1997) "The Roving Mind"


"After I give lectures - on almost any subject - I am often asked, 'Do you believe in UFOs?'. I'm always struck by how the question is phrased; the suggestions that this is a matter of believe and not evidence. I'm almost never asked "How good is the evidence that UFOs are alien spacships?'." - Carl Sagan, "The Demon Haunted World", p.78


These great quotes from Asimov and Sagan are sad, because it is so unnecessary for anyone to remain rooted in the "belief" orientation.... Einstein once said "the most incomprehensible thing about the universe is that it is comprehensible". It's a great quote, but not to be taken literally. Most scientists find it's actually much easier to see why the universe would be comprehensible to us. Here's why...


1. Natural Selection and the Development of Mind

The fossil record shows convincingly that life evolves. There's an unbroken sequence of subtle changes in the DNA of all species of life on Earth, showing the accumulating changes which has marked the adaptation of species to the environments of the Earth. Darwin and Wallace showed that this evolution is guided by the process of natural selection; members of a species are not born equal. Some are better able to solve the problems of survival than others. To some extent, these abilities are genetically inherited, so that those most successful will tend to survive and therefore leave more descendents which, to some extent, genetically inherit these higher skills and are therefore more successful as well. Those not as successful will tend to leave fewer descendents. Thus, over many generations, a species gets better and better adapted to its environment as a higher and higher fraction of its population is made up of better adapted individuals... We see this today in the news, with the over-use of antibiotics leading to drug-resistant strains of diseases. What's more, species evolve a unique "edge"; some ability which allows them to outcompete others within its ecological niche. For Homo Sapiens (that's us), that edge is our brain's ability to do conceptual reasoning to abstract principles by which the World operates. My point about Einstein's statement is - it's not surprising that our brains can comprehend the universe! If our brains hadn't evolved to be better and better equipped to understand reality, we likely wouldn't be here. The recent discovery of the phenomenon of epigenetics (an organism's ability to affect its heritable DNA by choices made during its life. Deeper descriptions here) is an interesting extension. Our human ability is the ability to observe events, abstract from them general principles which appear to govern these events, and further integrate these principles into wider knowledge in a way which gives you that "light bulb" experience (or the "click", as one of my students rephrased it) of non-contradictory synthesis of understanding. Our brains signal errors by giving us that clashing "doesn't fit" feeling (a "clack", we could say), like when you stare at 2+2=5. Think about that... it's really mental sensations that signal understanding vs contradiction. That's getting pretty organic and pretty biological. But these perceptions and integrations take biological energy, and because Nature has to be parsimonious in where to allocate the scarce resource of biological energy, the mental workings therefore don't happen without intent and focus. Unlike many other animals, our brains, especially our reasoning abilities, don't work unless we exert conscious effort. It takes biological energy to make a conscious decision to think, focus, and hold fast to the basic principle that the desire for truth must take precedence over all other temptations (like, being proved "right", or impressing someone else, or avoiding a painful realization, or indulging a questionable desire, or indeed anything else). Consider... skiing well requires great focus and effort but pays off with delightful feelings. Thinking clearly - likewise! It's exhilarating doing ANYTHING well. It is confirmation in reality of your competence, and competence has survival value and therefore can be expected to be rewarded in the most primal way.. Your brain produces the "light bulb" feeling when you integrate a new understanding into your previous knowledge without contradiction. And you get the "doesn't fit" clashing feeling when you stare at an idea which conflicts with your current knowledge. This dissonance is your organism's warning signal that you need to focus with greater attention resolve the conflict, that you're not yet in optimal contact with Reality. And, that "light bulb" feeling of resolution feels good when understanding finally comes. It's your organism's reward for doing a good job at integration. Those who spend a lot of time avoiding awareness by frying their brains on drugs, alcohol, and mindless TV, don't realize the fun and pleasure that your feelings give you when you do the right things mentally (they're also confusing genuine pleasure with numbing yourself to your pain. These are not the same thing.). We evolved these feelings as motivation and reward for successfully coping. Ask yourself how long a species would last if it were wired to give pleasure when it acted self-destructively, or didn't experience pleasure when it did things right. Avoiding the "pain" of effort or of sobering realizations, is not the same as genuine pleasure, and a continued pattern of avoidance of mental focus is a guaranteed path to deep anxiety, a feeling of being out of control, and then to depression (the organism's mental experience resulting from the conclusion that nothing you can do can help you. Depression can be lifted if you discover limitations in your assumptions, so that you discover you CAN help yourself in these regards. On the subject of depression, the first step will probably be to consciously make yourself open to exactly what you are feeling. There's no situation so hopeless as a situation at which you refuse to look. A good cry may be that first step).  

2. Using this in Learning


Wise students will use this fact... insist on the "light bulb" experience as you learn. If you're not getting it during lecture, stop me and ask me to explain it another way. And here's another important point: Realize that when you focus on a problem, when you really try to make sense out of something, and when you really care about understanding it, then even if you don't immediately succeed, your subconscious will continue the process of integration. It may be a day or three or longer, depending on how tough the problem is, and how tenacious you are in your desire, but at some point the "light bulb" will go on. You'll be washing the dishes and all of a sudden - "Ahhh! now I get it!". Trust in this process and don't be easily discouraged when understanding isn't immediate. It will come, but only if you're genuinely care and put forth the energy of focus. Conversely, if you aren't really interested in understanding it, it probably won't happen. Deep inside, it's the presence or absence of a true desire for clarity that will make or break this process. This is a big reason why people with a lot of curiosity do so much better at mastering new knowledge of all kinds. So here is one of the key points: You have to care. Or all is lost in the quest for understanding.


I swear the earth shall surely be complete
to him or her who shall be complete,
The earth remains jagged and broken only
to him or her who remains
jagged and broken.

-Walt Whitman


Consider this - suppose you've NOT insisted on the "light bulb" experience before letting something become part of your brain's established knowledge base. Your mind is then like a jumble of jagged pieces which aren't fitted together into a non-contradictory whole. What will it feel like if another undigested factoid is knocking at the door to join the rest? Clearly, it will feel no different than before - it's just another jagged, unintegrated, undigested thought. You'll not get that experiential signal that something is wrong - because you've never engaged the mechanism which tells you truth from falsehood. You've left yourself no means to judge truth. But now suppose you HAVE been careful in only letting in as knowledge that which fits without contradiction into a non-contradictory holistic knowledge base. If a new piece comes in which doesn't fit, you get a strong "clash" experience, the non-light bulb. And this is your cue to look more closely. Either the new "knowledge" is false, or perhaps (tragically!) your whole existing paradigm is false. If, when too young, you started building a mind of nonsense, and then kept feeding in more that reinforces it, you may have confused the "light bulb" experience with another sensation, which I'll call ...."this agrees with my prejudices (and I don't want to look too closely at whether my prejudices are valid or not)". Telling the two apart if you've never experienced the "light bulb" may be tricky. I continue to ponder how best to show that to students... You may not always get a clear "light bulb" when trying to grasp a new idea if you have not yet identified the "light bulb" as such. New knowledge accepted this way needs you to hang a big yellow flag on it. The flag being a sense that this is as yet not verified in your own mind, but seems to come from a reliable source and so you'll accept it as provisional knowledge.


Here's another aspect of learning. Understanding happens through the manipulation of your perceptions and internal representations of reality - not of the outside world directly. There are three broad categories that your internal representations can take: Visual (pictures and movies in your mind), Auditory (sounds in your head), and Kinesthetic (internal sensations of e.g. muscle movements, etc.). You ideally use these different modes to suit different contexts. For example, use your kinesthetic sense when learning how to swim, your auditory sense when learning poetry, and your visual sense when grasping most physical processes. Unfortunately, not understanding these distinctions, we can fall into a rut of going to one mode preferentially, even when it's not suited for the task . The best (worst!) example is a teacher's lecture at the front of the class getting processed internally by the students only on the given auditory level. In this case, a student's notes will only have words and no pictures. For the physical sciences, you want to use your visual mode: while I lecture, see images in your mind, see movies of processes. Words are only a handle for the real guts of it, which is a 3-D visual understanding. If you just copy words onto your notes and they don't convey any images, you're probably not getting the point. Fortunately, surveys indicate that roughly 2/3 of our society most often goes to the visual mode. That's good for learning science. I will use plenty of graphics in my powerpoints and on the whiteboards to help you along in class.


3. The "Real World"


We live in an objective, external world. In other words, we do not live in an ethereal personal dream/nightmare having no connection with an external reality. The fact that our sense organs and brains strongly filter that Reality does not change this fact. The truth of this is easy to prove - if you were living in a dream world, you would not be able to successfully get your basic life needs met so as to keep living... food, water, shelter, safety... your needs from the Real World. If you are not able to live, you are not able to dream your dream world. Q.E.D.! Also, if a person assumes otherwise, then logically they're at a dead end and, believing their mind to be lost in subjectivity, they have just disqualified themselves from making any trustworthy judgments on any subject, including their claim that external reality doesn't exist. Think about the simple but powerful logic of this! Those who make a similar claim by relying wholly on "blind faith" are in the same trap, since they still have to use their own judgment to decide which authority figure or authority book to invest their faith in, and there are many contradicting gurus. I make a distinction between "blind faith" and "rational faith" - the latter being the "faith" [trust, really] one has in sources which have already demonstrated to you a good track record for reliable inquiry. Clearly we don't have time to re-invent the wheel at every moment - rational faith has a place. But even then, the wise will clearly distinguish between what is first-hand knowledge and what is provisional knowledge accepted from other sources. The fact that our senses and perceptions severely filter our perceptions does not invalidate this simple truth. Understanding those filters by testing our understandings against the evidence, allows us to overcome them.

Let's pause on the concept of a contradiction. A contradiction is a statement with two or more ideas which are logically incompatible, which cannot both be true. A contradiction is easiest to show in a closed system. Your mind signals you that you're seeing a contradiction with a strong "that does not compute!" experience, which has a different feel than a "that disagrees with ideas which I've accepted but, to be truthful, I don't have a first-hand complete grasp of" feeling. A closed system is a system of knowledge all of whose distinct, independent axioms are specified, usually because they are defined by us. An open system is one in which the principles are not defined by us and not necessarily completely known. Mathematics is an example of a closed system: For example, once we define the concepts of 2 and 4, and the concept of addition, then the statement 2+2=4 is a logical truth which can be proved. All sciences, however, are open systems - there's no "instructor's version" with the answers in the back. This is because it is Nature, not us, which determines what principles guide the processes of the World which we observe. We will perhaps never have absolute certainty that all relevant principles have been discovered by us. Now, in both open and closed systems, contradictions cannot exist. In the case of closed systems, this is "by construction". In science, it must be assumed to be true, because assuming contradictions exist is really stating that our minds are not suited to understanding the real world, and this is a self-contradictory statement as we saw above. More, the history of science shows over and over that what may appear
to be, or rather too-quickly labeled as, a contradiction, will disappear when looked at more closely.


The Supernatural
If contradictions do not exist, then there is no explanatory power provided by the idea of a "Supernatural". There is only that which is real, whether discovered and understood yet, or not. That which is real will fit together without contradiction. That is also what we call - the natural. We have seen time after time that apparent contradictions resolve into a new and wider non-contradictory understanding when we bring enough focus, observation and effort to their study. Sometimes people think of the supernatural as simply that which is beyond our (current!) explanations, but this is a dangerously poor choice of words. There is certainly plenty that we don't understand, and as much as we learn there will no doubt always remain lots more that's not yet understood. The danger of using the term "supernatural" in this context is that it covers up the fact that that which is not understood must still be explainable in a way which does not violate our past and future observations. It may violate our present ideas, because ideas, after all, can be wrong. (more on
this below), but never our observations. Observations are Mother Nature talking to us. We need to listen. In other words, be a little more humble, don't be so quick to say that NO natural explanation is ever going to be possible and therefore it must be "supernatural". The worst aspect of letting in the notion of the Supernatural is that, both within our own minds, and in a societal sense, it shuts down curiosity and motivation to continue seeking natural explanations. Labeling something "supernatural" tends to stop further inquiry, rather than encourage it.


4. Scientific Method


"We are certainly not to relinquish the evidence of experiments for the sake of dreams and vain fictions of our own devising" - Isaac Newton

The steps of the scientific method have been evolved and condensed as the most efficient way we have discovered for gaining the "light bulb" biological experience of understanding, and for ruling out ideas incompatible with Reality.


All of us, scientists or not, are constantly making observations. Through your curiosity, eventually you notice a set of apparently related phenomena and form a question about it. You then brainstorm, coming up with any possible explanatory models. These models, at this point, are called hypotheses. We haven't used any rigorous logic yet, and shouldn't. This is the time to be wild and crazy as necessary. As the great Nobel physicist Richard Feynman says, on how to formulate ideas - "You guess". Maybe you'll have a good long list of hypotheses at this point. Take your hunch of the best one (Occam's Razor - see below - has shown to be a good rule-of-thumb to begin that) and visualize the meaning of it as clearly as possible, so that you can see what the observable consequences would be. These observable consequences also should, ideally, be objectively observable, meaning visible to others in the outside world. Then you test your hypothesis by designing an experiment which looks for these consequences and distinguishes against other consequences. This is where you have to be hard-headed and logical. If a hypothesis fails a test, even just one test, then your hypothesis is ruled out. You breathe a sigh of relief, you've made progress! The list of possible models is now shorter! You keep this circle going until you find a hypothesis which passes all your tests. If it passes all tests so far put to it, a hypothesis graduates to become a theory. At this point, if you're in the science business, you may talk to your colleagues down the hall about your idea. If they can't pick any holes in it, you're encouraged and take your show on the road, giving guest colloquiums and seminars at other research centers. If your theory's still standing, you write up a paper for publication in a peer-reviewed scientific journal. This becomes an open invitation for all scientists to see if they can devise new ways to test it, or consider aspects which you may have overlooked. The first thing that is usually done by other scientists, especially if the claim is important and surprising, is to simply repeat your experiments. If they can't be repeated, then interest usually fades. But if it's repeatable, and passes all tests that anyone can devise, it may become part of the current paradigm; our "best current theory". The popular press often presents such a theory as Final Truth. Scientists are clear in their own minds that their latest theories are always subject to revision as might be required in light of new observations. The only requirement is that revised theories must agree with all validated observations, even the old ones. But when science gets reported by a scientifically illiterate media, this aspect is usually left out, and the lay public gets the mistaken impression that scientists are arrogant know-it-all's. (Why? As far as I can judge, because real journalism is a fading art, and because most journalists don't understand what science is, and, frankly, they feel it sells better when you hype it up). A good scientist will happily tell you what's pretty firmly established and what isn't. Again, it is observations and not theories that remain sacred. Hypotheses come and go. Theories are usually more robust - as observations mount, it often becomes more and more difficult to avoid a certain fairly narrow range of options for where a logically consistent proper explanation lies. Still, even theories can be overthrown. It just doesn't happen nearly as often as the popular press or New Age book writers might lead you to believe. Before getting miffed at science, be sure to read the original journal papers, not just the popular press. You may see a more carefully explained range for what is being claimed.   This brings up the next point. To stay well connected to what's real, you have to develop a tolerance for uncertainty. Or better, learn to love it, and appreciate the mystery! Those who are too anxious for certainty often succumb to taking whatever idea seems most comfortable, motivated more by the avoidance of anxiety than the desire for truth. On the other hand, I see the foes of scientific thinking being too quick to say "we know nothing", which can be refuted by simply looking around at the incredible advances in our technological world. Good science says no more - and no less - than the evidence demands. Non-scientists are often too tempted to either assume "X is proven" or "We know almost nothing about X". The popular media doesn't help in this regard. The media likes to sensationalize by taking about an interesting discovery as overturning the current paradigm, (it sells!) but this is almost never true. Things just are NOT so black and white. .   The art of science is to use your powers of reasoning and observation to find the most promising ideas of how things work, and to weed out what conflicts with the evidence.  Mistakes will be made. But the method remains solid, and mistakes are usually found quickly. Those who are too afraid of making mistakes rarely do original, independent, and ground-breaking work in science or anywhere else. But the converse is also true - those who insist on putting their chips on ideas disfavored by the evidence, are nearly always shot down.  

5. Steps of the Scientific Method

1. Observations lead to a...
2. Question, on which you brainstorm for a...
3. Hypothesis, which you then get logical and hard-headed about and...
4. Test for Observable Consequences, which if failed, take you back to #3, and if passed lead back to #4 over and over until
you run out of do-able tests that are possible to do, so far as you can tell. If it's still standing you have a...
5. Theory!

Few ideas can be said with absolute finality to be final "Truth", because it's usually impossible to know if you've exhausted all possible tests or all possible alternate ideas. So, what we seek are ways we can rule hypotheses out as being inconsistent with observations. At the end of that process, you can at least hope there's only one compelling idea left standing! For example, consider the Steady State Theory of cosmology, which hung around in various forms for hundreds of years before finally being ruled out by observations in the 1960's.   Now here's two properties of a well formed scientific theory or hypothesis:   1. It must be falsifiable - meaning, there must be logical, observable consequences to this theory which, if failing observational test, rule it out. If all conceivable observations are compatible with the idea, then it is without consequences and without intelligible content. An idea only has content to the extent that it is observationally distinguished from other ideas. If there is no distinction, there is no scientific content, even if on the surface it may appear to be saying something.   2. At least some of its observable consequences hopefully should be unique. That means that no other known hypothesis produces the same observables.   From (1), we can hope to rule it out if it's wrong, and from (2), we can hope, if it's right, to realize it's a strong, realistic contender, justifying devoting our scarce resources of time and money to further investigating it. If your hypothesis has no observable consequences, then it's is not within the realm of inquiry! If none of your hypotheses have observable consequences, then their truth of falseness cannot be determined. Your hypothesis in this case is called speculation. For example, the claim that global warming is caused by some kind of unseen energy waves from a civilization on the planet Krypton circling a star in a distant galaxy, is not a scientific issue because we do not have the technology to test the existence of such a civilization out there. Which doesn't mean we can't find a sufficient explanation for global warming by looking at testable ideas instead. This next is really vital and rarely appreciated - one doesn't need a hypothesis about HOW an effect occurs in order to test whether it indeed occurs. This is a common misunderstanding with beginning students. A classic example is given by astrology. Natal astrology claims that your basic personality is influenced by the positions of the sun, moon and planets at the place and time of your birth. These are objective data and this is a very testable claim! It is premature to worry about HOW this planetary influence can happen, and in fact most astrologers don't try to explain how. The mechanism of the cause is not important at this point. First test if the claimed association between birth date/location and personality even exists. If it does, then (and only then) would it indeed be fascinating to try to discover the what and how of this mechanism. Some, including our former text author Andrew Fraknoi, bash astrology because the sun isn't even in the astrological signs claimed. Yes, but - so what? Since astrologers rarely try and claim a mechanism for why astrology should work, how can anyone claim that this birth sign offset actually kills astrology? It doesn't. What instead kills astrology is that there is no correlation between birth sign and personality, as numerous studies have shown.  

6. Characteristics of a Good Scientist
* Starts each investigation with a sincere over-riding desire to know the truth, whatever it may be
* Has a willingness to be wrong
* Is comfortable with uncertainty, even enjoys the adventure of it. Not over-anxious about it.
* Confines conclusions to the evidence. Inductive hypotheses are labeled as such.
* Performs a good error analysis so that the confidence level of the results and conclusions can be approximately quantified.
* Has a willingness to be emotionally uncomfortable with science-based conclusions, if that's where the evidence leads


7. Pseudo-Science


"What I seek to accomplish is to serve, with my feeble capacity, truth and justice at the risk of pleasing no one" - Albert Einstein

"We got here according to the laws of physics and we are subject to those laws and must live within them, We can't be guilty of magical thinking in predicting our future." - National Academy of Science member UCSC Astronomer Sandra Faber


When people use the trappings and jargon of science to lend an aura of credibility and high-mindedness to an otherwise bogus body of thought, we call this a pseudo-science. Pseudo-science is not hard to find at any bookstore. Healing crystals, pyramid power, astrology, Tarot cards, numerology, palm reading, channeling, past lives, homeopathy... the list is almost endless. The thing is, many of these are actually accessible to science. Meaning, they make claims which are visible in reality, and therefore test-able! The problem is, doing conclusive studies takes time, effort, and money. The proponents of pseudo-sciences have not shown the inclination to do such studies. Even more telling, when studies are done, the outcomes have no apparent effect on the followers (a number of good studies on the claims of astrologers have been done - all with unsurprising results - i.e. they fail. Astrology is of particular interest for an astronomy class, so I've assembled a webpage on what fair tests show about the validity of astrology.: Here's another well-designed fair test which astrologers failed. And here's a great resource from the Astronomical Society of the Pacific on the available scientific studies of astrology and other pseudo-science. It appears that believers believe these pseudo-sciences more out of a desire to feel connected to the universe at large in some magical way, and they allow this desire to take precedence over observed reality. Scientists, especially after these astrology studies, have understandably less interest in wasting further resources debunking pseudo-sciences, since the believers are apparently not swayed by the evidence of Nature anyway. Incredibly here in the 21st century, there is more money spent by people on astrology than all the funding for genuine scientific research in the United States. Pause, while that outrageous fact sinks in....... Some have argued that we are entering a new Dark Ages with a vast and growing gulf between the scientifically literate and the average lay person. I hope its not this bad.... but it might be.To oversimplify only slightly, to make a claim about Reality a scientist will respond with "Let's ask Nature herself". There are too many who do not want to look at the evidence before forming their beliefs. Note that there has been for over 40 years an offer from the magician James Randi, of (currently) $1 million, to anyone who can demonstrate the existence of anything paranormal. So far, there have been no takers. (He makes a good case that it is actually magicians who are better equipped than scientists to debunk the pseudo-science purveyors, since scientists are often too naive in the art of duplicity - being as they are, mostly dealing with other scientists).   The "light bulb" experience follows from a state of concentrated awareness and desire for clarity, and from the act of integrating new knowledge into carefully assembled existing knowledge without contradiction. Be on guard against a different kind of momentarily comfortable mental experience, which has an uneasy quality of awareness avoidance that's just under the surface. But ultimately, you'll only know the difference from your personal experience. We are all human and we all feel the sway of both at times. The wise person observes which is which. Certainly scientists can get attached to their pet theories as well. The difference is, if they let their attachment ruin their objectivity, they lose credibility, can no longer win grants, and other scientists will no longer take the effort to study their work. It's the ruthless logic of the scientific method which ultimately disciplines the field. Good scientists know that they sometimes must witness the "murder of beautiful theories by ugly facts", as it's humorously been put by scientists themselves. This isn't to say that there aren't wonderful insights to our understanding of life and the universe in some New Age material. Particularly in psychology - a very challenging young science since it demands incredible maturity and objectivity in that the subject of study is also the object of study - the mind and emotions. I believe academic psychology is often too simplistic, and the important advances have come from out of "left field", or what seemed like left field when first advanced.   I've always been curious about the motivations behind the popularity of so much pseudoscience. One motive I've heard is the feeling that scientists take all the magic out of life, reducing it to cold statistics. But this misunderstands science as nothing but factoids. Instead, consider the incredible discoveries of the last decade in my own field of astronomy. The astronomers I know will, every one, tell you their own experience is that, in the words of Jules Verne, "Reality provides us with facts so romantic that imagination itself could add nothing to them". Now, many are fond of the quote from Einstein "Imagination is more important than knowledge". It's true that major advances require the ability to imagine, and sometimes to think unconventionally. But ultimately, the results of imagination, to qualify as "knowledge", must be subjected to the rigors of scientific testing - asking Nature herself. There's a time both for free-floating imagination, and a time for hard-headed scientific testing. Einstein demonstrably knew this. We also should point out that the very word and context of "imagination" can be quite different between Einstein and the average person. Imagination carries with it the ability to vividly visualize and experience the logical meaning of the ideas you are pondering. It doesn't mean it's deuces wild on everything. What too few seem to appreciate, is the feeling of exhilaration and joy that comes from seeing your powers of reasoning confirmed by Nature, the joy of experiencing the confirmation that your mind really does work. Drug-of-choice induced anesthesia can't compare. While I'm tempted to say that hallucinogens are just a way to retreat from life, a friend recently pointed me to a reference showing a number of great scientists and great minds who have and even recommend some hallucinogens, including Steve Jobs. Since I've not tried them, I should resist my temptation to lecture anyone on this subject. My guess, however, is that these geniuses already had great minds, great passion and ability for thought, and that the drugs didn't turn them into vegetables. I've not personally seen this in anyone I know. I have, however, seen lives of resignation, wasting away on drugs.

My Sacred Opinion...
Too many of you have been given the impression that your opinion is sacred. That all opinions should be regarded as worthy of respect. The truth is otherwise. Mother Nature does not care about my opinion. And she doesn't care about yours either. My sacred opinion - it counts for nothing in the eyes of Mother Nature! Reality cares about only one thing - what is true. I've had it said to me at times "well that's just your opinion, Rick! It's not mine. My opinion is just as good as yours", or something similar. Will Mother Nature honor my or your sacred opinion- that's the real test. No. It is you and I who must align ourselves with Nature, objective Reality, not the other way around. We are not all equal and our opinions are not equally aligned with Nature, or worthy of being honored by the rest of us. It seems so obvious when stated this way, but yet so many people, young and old, have been coddled into the notion of being all-powerful in their wants and feelings. Nature, bluntly, just does not care. Once you really grasp that, you grow up, and you enter into a new relationship which is actually far more exciting and exhilarating You're no longer fighting what's true, banging your head against a World that does not obey your wishes, clinging stubbornly to a belief system which conflicts with the evidence. Instead recognize - we are pre-wired by evolution to find being in alignment with Truth to be experienced as pleasure, excitement, and a sense of really living.
And part of Truth is - Nature does not care about our opinions! This, of course, is not to say less about individuals. My point is that good people can hold opinions at variance with Reality. People should, if possible, be treated with respect, but not all ideas are so deserving. Psychologists have found that to over-identify with ideas about which you can have no confidence of their validity, is damaging to your self-confidence. Instead, align yourself only with the notion that you are willing and desiring to know the Truth, whatever it may turn out to be, as revealed by evidence.

There is also the cul-de-sac of the ~1990's Post-Modernist attacks on science as nothing more than social constructs, and which was exposed for its vacuity by physicist Alan Sokai (here, and more roastingly here).


7. General Principles in the Design of a Scientific Test

Astronomy is a bit unusual in that there's rarely a chance to set up situations and do full-bore controlled scientific testing like I describe below. But for most of you, these ideas below will be important to consider, for example, in evaluating the truth of medical claims, something we all are exposed to. Suppose you are to design an experiment to test the claim that taking beta carotene supplements will reduce the incidence of cancer (to take a classic publicized example). Here's some guidelines...  

You'll want to get a sample of people and give half of them beta carotene and half a placebo. A placebo, in this case, would be a pill that looks like a beta carotene pill but is in fact some inert ingredient already shown to be unrelated to cancer. Here's some considerations...


a. The placebo effect. The mind powerfully affects the body. Our thoughts and feelings affect health in ways we only are beginning to understand. If someone believes beta carotene works, and they take a pill they think is beta carotene, they may in fact induce poorly understood internal processes which may in fact lower their probability of getting cancer. More commonly and more importantly, the reality of taking action you think could well be effective has a huge effect on the perception of pain. Even "physical" pain has a large psychological component. Pain, after all, is our bodies signal to our conscience mind to "do something - we're in danger!". Once you believe you've done something useful (like taking a pill you believe will help, even if it is actually just a sugar pill), then your perceived pain can drop noticeably. This is why illnesses whose only symptoms are subjective perceptions require very careful science in order to evaluate properly. Both of these aspects are called the placebo effect. To guard against mistakenly assuming the healing was caused by beta carotene, you must be sure that not only does the subject not know which pill has beta carotene, but neither does the person giving him the pills. If the doctor knows he's giving placebos to one group and real pills to another, some subtle mannerisms may betray this to his patients and affect their expectations. A study done this way is called a "double blind" study. Neither doctor nor patient know if they're getting the real stuff.


b. Proper controls. A controlled study is a study where great care is taken to insure that any other factors which could conceivably affect the outcome are identified and kept constant so that the only variable is the one which is being tested. One way this is done in medicine is to match subjects in pairs. Divide your subject sample in half, and pair up each person with another who is as nearly identical in relevant aspects as possible. Then for all pairs, give one the real medicine and one the placebo. For example, suppose the cancers you're testing occur in women more often than in men. If you don't separately record the gender of each subject and properly match the test subjects with the placebo subjects, then you could mistakenly infer an effect due to beta carotene which is in fact due to gender differences.


c. Sufficient sample size. There may be many causes for cancer. Our hypothesis is only that beta carotene will reduce cancer incidence, not eliminate it. If Aunt Mabel takes her beta carotene every day and lives to age 100 before she dies of kidney failure, this is NOT evidence that beta carotene works! Nothing can be argued from a sample size of 1. If we claim that beta carotene will reduce cancer incidence by 20%, then to oversimplify just a little, you'll need at least 100 people in your sample. To be properly controlled, that means you'll need 100 people who are alike in every possible way which could influence their cancer risk. Since it's hard to know every possible cause ahead of time, in fact you'll need to start with a much larger sample and do the subcategorizing later. Also, having "95% confidence" in your result is considered a bare minimum to qualify as reasonably conclusive. If you want 99% confidence, you'll need to begin with at least 1000 people. Since this is expensive, many studies do not have such large samples. But in this case, fair-minded authors will only claim their results to be "suggestive" rather than "proof", and thus invite further studies to improve the statistics.


d. Random sample selection. You must be sure your sample is random with respect to what you're measuring. If you're measuring the occurrence rate of breast cancer in the U.S., you'd want to select people randomly from the entire U.S. population. You wouldn't want to go to the cancer ward at the local hospital to find your volunteers; you'll get a very alarming cancer rate! If you're testing the pain-control effect of some new medicine, you wouldn't want to go to a New Age health conference to get your subject sample - you'll probably get an exaggerated placebo effect that you'll need to disentangle.


e. Sufficient time. Run the test as long as you believe the effect could take to appear. For cancer, we know it may take many years from cause to malignancy.


f. "Associated" does not necessarily mean "caused". This one is really unappreciated by the popular press. You may assume one thing caused another, when in fact both things are caused by a third. The mind itself will be very tempted to do this. In the simpler world of most of our evolution, it was handy to make snap judgments that if Y followed X, then Y was probably caused by X. So be careful. Suppose you do a study and find with high statistical significance (more than 99.99%) that roosters begin crowing at the same time as crickets stop chirping. Did the quieting of the crickets cause the roosters to crow? Possibly, but better re-check your data and see if maybe the sun coming up at the same time could instead be the cause of both. Another way this same truism is stated is "correlation is not necessarily causation". True enough. However - be clear on this - that if there is NO correlation between two sets of phenomena, then there is NO evidence of causation, and there is nothing requiring explanatory mechanisms. Correlation here also means anti-correlation. For example, suppose you are testing the hypothesis that white button mushrooms cause death, while Jack o' lantern mushrooms promote good health. You give half your sample white button mushrooms and find their energy levels increase and their health remains good, while the sample half that got the Jack o' lanterns mostly died. Then you have an ANTI-correlation between Jack o'Lantern eating and good health, opposite to your hypothesis. That still means that there is a strong health-affecting aspect to Jack o' lanterns. Suppose instead that there was no difference in the health outcomes of either side of the test. The statistics didn't show health to be affected differently for white button mushroom consumers vs. Jack o'lantern mushroom consumers. Then in this case, there is nothing needing explanation as to how mushrooms could affect health. This could be carried over to astrology. The fact that there is, in fact, no correlation between birth time and birth place with personality, means that there is no evidence of anything requiring explanation. There is no point speculating about mysterious forces undiscovered by science because there is no phenomenon requiring any explanation by hypothetical mysterious forces.


g. Don't overinterpret the data. This one is a common pit-fall lurking in alternative medical claims. For example, it can be tempting to look at, say, a medical practice which provides symptom relief and assume this provides support for an entire paradigm which includes this practice. Yet the medical practice itself may have no logically necessary relation to the paradigm. Consider a Native American practice of grinding and eating willow tree bark to banish the evil spirits showing themselves as what we'd call inflammation and pain. And you find with good scientific tests that this willow tree bark really does lead to pain relief far beyond that predicted by random chance after controlling for placebo etc. Does this provide support for the evil spirit paradigm? No, it only provides support that this willow bark can relieve pain. Maybe it's the salicylic acid (aspirin!) which is found in willow bark which is the active ingredient.


8. Occam's Razor and Sagan's Corollary

This is a principle in science named after Lord William of Occam. We've noticed over and over that, given two or more explanations, all of which explain the observations, the one which ultimately will most likely pass the tests is the one which requires the least changes to current thinking. In other words, "simpler is usually truer". Perhaps the ultimate reason that this seems to be true is that our brains really are evolved to work well at understanding nature. Carl Sagan identified a complementary principle of good science, now called Sagan's Corollary: "extraordinary claims require extraordinary evidence" (a famous quote of Carl Sagan). Occam's Razor is what chops down the UFO sightings. 99%+ of UFO sightings can be explained more simply as e.g. the planet Venus twinkling through turbulent air, or large meteors or military aircraft, ball lightening, wishful thinking, etc.... if not out-right hoaxes. The alien abductee stories can be more simply explained as attention- (or money-) getting frauds, or self-induced hypnosis. Also, the relaying of the story from source to eventual publication often gets subtly, or not so subtly, distorted.... The old "fish story" phenomenon.

Finally, when a body of evidence points in one direction, then a claim which points in a vastly different direction should, by fairness, be required to produce stronger evidence before being given credibility. If this is not done, one can end up with the the "truth" walking away from actual Truth by halves, for every bogus claim advanced. A kind of Zeno's Paradox towards unreality. This is a common tactic of climate denialists, who barrage good science with bogus lies, counting on the human tendency (when confronted by baffling incomprehension) to split the difference and figure truth is somewhere between competing claims.

9. Expectation and Perception

Appreciate how much our expectations influence how we "see" what we see. Too often we see what we expect to see. Go to the Exploratorium in San Francisco, or (more unscrupulously) the Mystery Spot up in the mountains here in Santa Cruz to see this in action. And listen to this entertaining episode of RadioLab (use the slider and click on "Stochasticity"). The brain so much wants to make sense out of what it perceives that if that person has no prior category for the sensory input, it'll force it into a category more familiar (even if only from the National Enquirer). Magicians use this to their advantage. Many people don't understand how differential refraction causes bright objects like Venus or Sirius to rapidly twinkle through many colors, so they may think they're seeing flashing lights of an alien spaceship (since everybody's seen Spielberg's "Close Encounters" and similar movies). I and other astronomers I know will be quite happily amazed and delighted if someone finds solid evidence indeed that aliens have or are visiting Earth. Till then, I'll keep my hand on my wallet. Still, the barrage of stories exceeds the manpower available to debunk them all, and this lets unscrupulous people sell bogus books, tapes, UFO conferences, etc. claiming the "unexplained" is actually the fantastic, the paranormal, or the supernatural. If you realize this tendency, you can give conscious focus to see what you're seeing as neither more nor less than it really is. Don't over-interpret the observations.


A good link on the popular stereotypes about science and scientists.

YouTube these days has many great video interviews and presentations by many of the great minds of the recent past and present. I've made links to interesting video talks from great thinkers; a list which will morph as I discover more. While the material here is not required for my exams, if you are intrigued by the ideas behind thinking, learning, science, and philosophy, then I think you'll enjoy listening to many of these.

The brain is like a muscle; active focused thinking makes your brain grow new neurons and improves your thinking. Here is a source on strategies from one of the pioneers in this new science of neuroplasticity.

And Finally...

Check out this discussion and consider these statistics from "The Age of American Unreason" by Susan Jacoby...

* 1/3 of Americans believe in astrology
* Despite the massive evidence of geology, physics, and biology, 45% of Americans believe that evolution by natural selection is just a "belief", and that it is wrong.

Realize that ~89% of American middle school teachers of science - have no science degree. Pause, and read that again. Half the people in the U.S. think that there was a time when humans and dinosaurs shared the planet together. Do you want great science teaching? Encourage real scientists to be teachers! They have unique first-hand experience and one-of-a-kind valuable insight to give. Let them give it. Stop trying to confine teachers to the tiny box containing the comfort zone of unenlightened bureaucrats and administrators, whose dream is a one-size-fits-all interchangable system where all individuality is stamped out and every teacher in the State system is an interchangable cog in a giant machine. Is THAT going to encourage great science people to enter education? Otherwise, we risk motivating good scientists to flee from education, regardless of the pay. We end up with students who's only experience with science is being stared down uncomfortably by a K-14 teacher who doesn't know the answer to their question. Our whole educational system is run by (documented evidence shows!) the least intelligent degree holders in the country, with mindless rubrics and pseudo-scientific number-crunching substituting for inspired teaching by mentored example.

So many young people come to me with questions on how to think about the World at large, what it means to find one's calling, to feel good about their place in the world. Check out these excellent presentations on the true nature of self esteem, and also here, and here. It's not built by unconditional flattery such as some well-meaning but under-prepared teachers may lead you to believe. Self esteem comes from a consistent policy of honesty and integrity and having "what is the truth?" as one's #1 priority. Only this can lead to growing self-trust and self-value (and also, only from this can come genuine generosity of spirit towards deserving others).
On that note.... learn to drop the scales from your eyes and take a fresh look at the universe. The moral is - Practice "safe concluding" - be careful about what ideas you allow to be accepted into your brain. And when someone makes a claim, demand evidence and reason.