Educating for the serendipitous discovery

As a result, a student who has obtained a degree in the sciences may ... a technirally competent prrson,or a highly skilled technician, it may not pro...
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Educating for the Serendipitous Discovery Ronald S. Lenox Armstrong World Industries. Lancaster, PA 17604 The typical science course in an undergraduate or graduate curriculum generally presents t o students a body of facts, a particular method of correlating those facts, and the techniques commonly used by scientists in that field t o collect data. As a result, a student who has obtained a degree in the sciences may possess quite a bit of factual knowledge about his or her field of study. However, acquisition of factual knowledge and development of expertise in methodology and technique do not tutally prepare one to function as a scientist. Indeed, one m~ghtarApe [hat while such preparation produres a technirally competent prrson,or a highly skilled technician, it may not produce a truly creative scientist. Traditionally, beginning students in the sciences are exposed to the so-called traditional scientific method. One presentation of this method from a recent undergraduate chemistry text ( I ) takes the following form: 1) Obtaining data. 2) Correlating data in terms of a law (a generalization correlating the behavior of some aspect of the physical environment). 3) Developing a hypothesis to account for the law. 4) Testing the predictive power of the hypothesis. 5) Formulatine theorv if the hvoothesis is found to me- a general " .. dict correctly. While this method effectively presents the process followed by many scientists when investigating a problem, it really tells students nothing about how scientists arriue a t the first step of the process. In other words, how does a scientist decide what data to collect or what particular problem to investigate? Why can one scientist he particularly creative in an area of research where others have been uncreative? The phenomenon of scientific creativity is rarely examined in any detail in undergraduate or graduate science courses, yet it plays a most important role in allowing one to function as an effective and nroductive scientist. Writine a research nrooosal . . for the first time can be a traumatic experience for young scientists. Generally, there seem to be three primary methods by which successful scientists are led to examine particular nrohlems or to oose swecific and correct solutions for existine problems. ~ h e i i r s df t these is perhaps the easiest to unde; stand and that is the method that might be termed, if we allow ourselves to borrow a phruse from atomic physlrs, the Aufhau or building-uu method. O ~ Ldeveluped . hs~uthesisleads to another and perhaps yet another ielatedbypothesis. The collection of data can become a routine, subject t o the ability of the investsigator to design appropriate new experiments. This type of creativity is often evidenced by students in undergraduate and graduate science courses. In an organic chemistry course, it might be typified by the student who asks, for example, if ferrocene and other aromatic sandwich compounds undergo the same substitution reactions as benzene, the simplest aromatic species. The second method by which scientists are led to specific problems and solutions results from what can at best be termed insight. This mode of discovery is less easy to understand and is certainly more difficult to address effectively in wienre curricula. Perhiips the best account oithis method is that given recently by two British scientists (2) who discuss the importance of flashes of insight that can occur during dreams, dream-like states, or even during walks in the country. The case of August Kekul6 and his proposal for the structure of the benzene molecule is probably the most widely known

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example of a discovery resulting from insight and reverie (2, 3). There are, moreover, many other documented examples. Although Goodyear's discovery of vulcanization is usually described as accidental, there is evidence to support the contention that he believed that he had a dream or revelation in whirh he w a u)ld to examine sulfur r2,4). Darwin reported in a letter to a friend that his theow oievolutkm first occurred as a "sudden flash" of insight (5): The third and last method. which has been of ereat importance and interest to the scientist, has been the method of chance or serendioitous discoverv. Manv such discoveries have heen part of the rerord of scienre. I t is not the purpose of this oaDer to examine in detail the rerord of these discov. eries and the means by which they came about but to discuss appropriate learning experiences for the undergraduate sEikncL student so that h e m she is more likely to benefit from this method of scientific discovery as he or she makes a career in his chosen field. ~~

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Chance Discoveries in Science William Paley, a moral philosopher and theologian of the late 18th centurv. noted that "there must he chance in the midst of design; bywhich we mean that events which are not desiened necessarilv arise from the pursuit of events which " are designed." Horace Walpole first proposed the term serendivitv for such"not-desiened" events in a letter LO Horace ~ a ik n 1754 after readigg a fairy tale titled "The Three Princes of Serendip." Serendip was the ancient name of Ceylon and the princes, according to Walpole, "were always making discoveries by accident, of things they were not in quest of." Robert K. Merton has applied this term to accidental discovery in science and speaks of a "serendipity pattern" that is and has been part of the record of the natural sciences (6). In examining the record of discovery in the natural sciences, one is indeed struck by this pattern. Friedrich Wohler, working in 1828, bridged the supposed differences between organic and inorganic substances by making a chance observation (7). A translation ( 7 ) of his own words describes his discovery: "The fact that in the union of these substances they awnear to chame their nature and pive rise to a new bodv. ..drew my attention anew to this substance and gave the unexpected result that bv the combination of cvanic acid with ammonia. urea is formed." Likewise. the German scientist Ronteen and his discoverv power of X-rays in-1895 arose from thk of the accidental observation that a screen coated with a fluorescent material glowed when placed outside a Crooke's tube. Rbntgen determined in further experiments that these rays were able glass, and even human tissue (7). to penetrate wood, The discovery of the radioactivity of uranium may also be described as an example of serendipitous discovery. The French physicist Henri Becquerel attemptedto establish some connection between X-rays and phosphorescence. While he did not discover such a connection, he did make the very important chance discovery that when a uranium salt was placed upon a photographic plate that was inside an opaque wrapper, an impression was formed on the photographic plate. This occurred when the sky was overcast and the sun did not apparently shine directly on the saltgto cause phosphorescence. &.

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This chance discovery led Becquerel to other experiments and finally to the conclusion that the atoms themselves emit radiation; this was the beginning of the study of radioactivity. I t is noteworthy that the discoveries of Rontgen and Becquerel, which occurred over a short period of time, had a profound influence on the development of both modern physics and our current understandmg of atomic structure. Serendipity has also played an important role in other areas of science. In 1848,Louis Pasteur accomplished the first resolution of a racemic mixture into its enantiomeric components by mechanically separating dissymmetric (mirror image) crystals of sodium ammonium tartrate that formed upon evaporation of water from a solution of the salt. Fortunately, Pasteur was working in the cool Parisian climate, for i t is only below 2I0C that this particular salt will crystallize into a racemic mixture of disvmmetric crvstals. Above this temnerature, i t crystallizes as a single compound that cannot be separated mechanicallv (8).Had Pasteur worked in a warmer climate or during a different season of the year, i t is unlikely that this discovery would have been made. In 1930,two New York gynecologists made the observation that fresh human semen was expelled from a human uterus during attempts t o induce pregnancy by artificial insemination (9). In later years, other workers followed this discovery with work of their own. Ultimately this led to the isolation and investigation of the prostaglandins, an extremely important class of hormones believed to be involved in many biological processes. Perhaps the best known case of serendipity in all of science is the discovery of penicillin by Alexander Fleming. While examining bacterial cultures, Fleming noticed that some of the Petri dishes had been contaminated by a mold around which the colonies of bacteria had been destroyed. Fleming immediately placed samples of the mold in growthmedia and verified his ohservation. Further investieatiou into the nature of the mold and its metabolites led to the discovery of penicillin. althoueh it was not until thecrucial need for antibiotics arose in the-second World War that penicillin was finally develoned commerciallv. Merlin Prvce. a co-worker of (10) about the initial discovery: "What ~ l e m i n ~ 'remarked s, struck me was that he didn't confine himself to observine but took action at once. Lots of people observe a phenom&on, feeling that it may be imnortant, hut thev don't get - bevond b e i ~ ~ & ~ r i s e d L a f twhich, er they forget7' Many other examples of chance discovery are known. Luigi Galvani observed the twitching of a frog leg suspended from copper wires when the leg was accidentally b r o u ~ h tinto vontact with iron. This discovery ultimately led to the creation of the hattery by Alessandro Volta. Charles Ricet, the French physiologiit, d i s k r e d quite by accident that he could induce sensitization to a toxic sul)stance; from this study came our understandine of allereies. The discoverv of vitamin K bv Dam, the syntkesis of tce f i t dye from aniine by Perkin, L d the discoverv of nolarization of lieht bv reflection made bv Malaus are ithe; examples of serendipitous discovery. ~ h " e list, i t seems, can be made almost endless. Educating for the Chance Discovery

If chance discovery is such an important phenomenon in the natural sciences. how then should one desien an undergraduate science cu;riculum t o ensure that stuzents will he more likelv to make a chance observation and be able to recognize the significance of it? Perhaps we might alsu ask uurs ~ l r e s "What . makes one scientist oarticularlv. rood ahout utilizing chance discoveries and anoiher not so good?" While one's area of work may certainly lead to more occasions for chance discovery, all scientists certainly have the opportunity t o make serendipitous finds. The first a r e a h which training for the chance discovery is possible in an undergraduate science curriculum is in the

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making and recordinz of observations. While most teachers of science would argue that they do attempt todevelop in their students the habit of observing and recording phenomena, there are too many occasions in which little or no reinforcement is provided for this most important hahit. This is often true in first-year courses-general courses. In the author's view, the most glaring deficiency is the use of the preprinted tear-out lahoratory report form which is frequently used in the teaching laboratory. When a student is instructed by a lahoratory manual, for example, to mix two chemicals and in the preprinted laboratory report he is asked to write down only the color that results, he is not being trained to observe properly. He will not, because of the direction to look only a t color, be bkely to observe or record the evolution of heat or of a gas. Only the color will be of significance to him. The result is that the student is being taught to see and not to observe. Likewise, instructing a student to look only at one set of variables in order to save time or to nermit more exercises to he done in a laboratory also leads toihe development of poor observational habits. Later, he mav feel uncomfortable when asked to make observations on his bwn and without direction; he will probably do an inadequate job. Instead, the habit of observing and recording should he taught by requiring the student to keep a regular laboratory notebook. Not only does this require a decision as to what to record, but it forces a student to observe carefullv and critically. The notebook should be read by the instruc&r not only for "correct" answers but for recording skills. In almost all sciences laboratory exercises can be designed that will enable a student to learn how to observe. Perhaps one of the best beginning exercises that has come to the author's attention is the simple, but instructive, practice of sealine an obiect (clothesnin. nlastic huildine hlock. etc.) in a b o x r ~ h eobjective for he'siudent is to d L r m i d e thk nature of the ohiect without o ~ e n i n the e box. Does the obiect roll? Does i t have corners? ~ o e itslide s smoothly? DO& i t have a ereat deal of mass? Bv forcine a student to devise methorls of gathering data and to scr;'thnmgh the data fur relevant and relnted nieces uf useful information. he can he convinced that he i i indeed capable of solving problems creativelv. From such an exercise, it is easy to progress to more pertinent ones. The identification of simple substances such as sugar, salt, or iron in a mixture containing several of these substances is an example of such an exercise. A student is allowed to find, observe, and record the physical and chemical properties of each substance in its pure form and then to investigate the properties of his unknown mixture. By correlating the properties of his mixture with those he both observed and recorded for the pure substances, he can deduce the constituents of his unknown mixture. The need for good ohservation and accurate recordine are soon evident: more complicatnl 1:~homtoryexercises h a y then he done with neater care and concrrn. I n d r d the student should be mided through all of his or her undergraduate coursework insuch a manner. I n every course, the student's modes of both observation and discovery should be examined, questioned, and shared with classmates. The second way in which an undergraduate student can be helped to develop as a discoverer is to provide some tvue of longer-term, structured research situat;on. This may i&olve a formal research program with a facultv member or a coonerative experience with an industry, or i t might be a part bf a laboratory program associated with a course. Nevertheless, n student needs to be a part ot such 3 program in which independent discovery and development of his or her own ideas and observations are the eoali. I t should he noted here that rediscovering a previously known fact by whatever route can be iust as excitine and instructive for an undereraduate student as finding something completely new. ~ e i e a r c hinto or investigation of any area unknown to a student forces the

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student to rely on his or her own resources; the student's success will depend on his or her efforts, powers of observation, and skill. Making a discovery in a realistic research situation teaches a student that discovery can be done and that the process is exciting. Obviously, guidance from an experienced and enthusiastic scientist is needed in many cases to help the student through those periods of intellectual "drought" that plague all of us. At the end of a research program, the student should then he asked to explain what he or she found and, most importantly, how he or she found it. A discussion of a laboratory notebook or a classroom conversation are excellent ways of involving students. The student should he able to share his or her excitement. An analysis of how a research program proceeded is an excellent way of demonstrating that discoveries are not alwavs nlauned. In too manv cases. a student's reading of tents or scientiilc papers can'lrad him or her to be1iet.e that all oublished result5 haw heen the workofcareful planning. M& authors present their results in such a way that one is led to believe that the entire oroiect was logicallv obvious from thestart and that theauthJronly roller& data 10 verify his hvpothesis. I'resentinp material to the scientific commu"ity in-such a way that the ;dual process of discovery is omitted or hidden from colleagues has been termed "retrospective falsification" (11). While a scientist may be unwilling or even embarrassed to admit that his or her results are perhaps the work of chance discovery, he or she does a disservice to the scientific community a t large and to students in particular by not sharing a true example of the discovery process. Allied to the concent of serendioitous discoverv is flexihilitv of thought. Woodb&n and O'~o&nhave stated(l2) that "to he sensitive to unexoected clues. the scientist must be able to al~sorl,and retrieve his knowledg.e without having it too firmly locked into fixed ideas."'l'he investigator who looks onlv for what he or she believes will happenls less likely to obs&e some other occurrence. Even if he or she does, he or she is less likely to attach any significance to it. The habit of contemplating all observatiohs, even those which are only minor v&iati& of the "expected" results, needs to be instilled in all students. The idea that "the experiment didn't work" is all too common in undergraduate (and sometimes graduate) laboratory students. Every experiment tells the researcher something; it is essential to discuss this concept with students and to make it a part of the philosophy of every lahoratory program. When a student tells us that his or her experiment "didn't work," he or she should be asked exactly what he or she means and what he or she recorded. Generally, the student who is following some standardized lahoratory procedure will indicate that he or she did not get the "expected" results. In the author's experience, manv students in this situation reallv are unable to sav . anv. thing about the actual results ezcept that they did not see what they wanted (or expected) to see. No true observations have been made and little or no contemplation of the experiment has occurred. This is precisely the time to initiate a discussion, not only with the student in question, hut perhaps also with the entire class. on the ~ h i l o s.o . ~ hofv open-mindedness and inquisitiveness. Perhaps the most important attrihute that must become part of every scientist's methodology, if he or she is to benefit from serendipity or other methods of discovery, is rigorous preparation before attempting to investigate a prohlem. The American physicist Joseph Henry voiced this necessity when he stated that "the seeds of great discovery are constantly floating around us, but they only take root in minds well .nreoared . to receive them." Louis Pasteur set forth the same idea with his now famous dictum, "Dans les champs de I'observation, le hasard ne favorise que les esprits pr6par6s." If Fleming's discovery of penicillin is reexamined in light of this philosophy, one is struck by the fact that he was indeed 284

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looking for an antibacterial agent at the time he accidentallv discovered the antibacterial mild. In addition, it is certain that he was extremely well read and trained in his field. Fleming was a good observer and recorder; he was well prepared and primed for his discoverv-of oenicurious; he was completelv .. . cillin. Graduate schools of science have invariably taught their students the benefits of rigorous preparation. Reading literature, attendinx research meetings, and listenins to seminars will constantlykxpose graduate students and practicing scientists to new and important ideas in their disciplines. This is probably the best of the ways in which science educaton are currently doing an excellent job of teaching and preparing graduate students for the chance discoverv. However. unaergraduate students of the sciences normkly do not,' and probably should not, receive this intensive exposure to specific subdisciplines. Undergraduate preparation has traditionally been in hroad areas of a general scientific discipline. In physics departments, for example, courses such as electronics, mechanics, and relativitv are offered while chemistrv deoartments traditionally teach organic, analytical, physical; and inorganic chemistry. This hroad preparation is necessary if later specific preparation a t the graduate or professional level is to be effective, meaningful, or even possible for the scientist. We can, however, introduce the habit of and useful techniques for proper preparation t o the undergraduate student in such a way that it does not detract from or interfere with his general education. Providing some introduction to the literature of any body of science is a necessity and this can easilv he creativelv incornorated into a four-vear colleee science curriculum. Senior seminars, undergraduate research oroiects and lihrarv assienments in courses can all serve this purpose. In many dkciplkes, such as English and history, the research paper has long been avital techniaue for teachinean undergrabiate student the importance of; literature investisation. In the physical sciences, however, there has been less emphasis on the reading of scientific literature and the writing of papers. Too frequently, students in the sciences can find their way through four years of undergraduate science courses by reading mainly textbooks and laboratory manuals. For many, graduate school or an industrial experience provides the first real demand for an independent and intensive reading and understanding of the scientific literature in their field. Without some practice or background knowledge concerning the use of the scientific literature, preparation and problem solving for such a person can he frustrating and inadequate. With some training and experience at the undergraduate level, i t need not be. One other attrihute is necessary both for educatingfor the chance discovery and for cultivating a genuine enthusiasm for science. That is avid curiosity. While some may argue that a scientific curiositv is innate. there is no doubt that the curiosity of one person and his enthusiasm for discovery have a nronounced effect on others. This is ~articularlvtrue in the student-teacher relationship. If a stGdent geniinely shares in the educational experience with a science teacher who exhibits a true scientific curiosity and who values such curiosity as a necessary part of his own scientific abilities, then the student will no doubt come to see the necessity of this as a part of a practicing scientist's "drivins force." A good teacher shouid try to develop this trait in students as much as possible. This means that a teacher must be more than a classroom figure. He or she must be an active participant in the scientific process and ought to formulate and attempt to solve problems in his own discipline. The teacher should read the literature and share with students his or her own chance discoveries and insights. In short, the teacher should function as a model for students both in and out of the classroom. A good teacher of

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science should be the very model of insatiable scientific curiosity. Conclusion Serendipitous or chance discovery is one of the important avenues for discoverv in the sciences. As such. it is imoortant to recognize it and to educate students of sdience in'such a way so as to maximize their chances of benefitting from such discoveries during their years as functioning scientists. Some areas that can be emphasized in the educational process, particularly in undergradate curricula, are the making and recnrding of observations, the provision of dvnamic structured research-opportunities, the ekouragernent of tlexibility of thought, the development of true curiosity, and the discussion of modes of discoviry. Not only do these methods work to the student's benefit in the area of serendipitous discovery, but they should serve the student well inall other aven"& of discovery and creativity. The truly successful scientist will no doubt benefit from all modes of discovery. It is the task of the science educator to ensure that his students are prepared in the best possible manner for discovery.

Acknowledgment The author wishes to t h a n k ~ r t h uD. r Hickman for his assistance in the preparation of this manuscript. Literature Cited 11) Maciel. G.E..lhkante,D. D., and Laud1oe.D.."Chemistry: D. C. Heahand Co.. Lexington. MA. 1978, p. 11. (2) Brow, R.A.,andLuckexk,R G., J.C-. EDUC., 55,694 (1978). (3) Bmfey.0. T.,J.CHEM. EDUC., 36.21 (1958). (4) Clarke, B. E. O.,"ChristianScieneeandBelief:English UniverjitiesPma.London.

Sfhwartz,G.. and Bishop, P.W.,(Editors),"The Developmeot of Modem Science: Bsaic Baoka, Ine., New York, 1958,pp.839and884. (8) Eliel, E. L., "Stereochemiatryof Carban Compwnds," MeCraw-Kll, New Ymk, 1962. (7)

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(9) Kumok,R., and Lieb, C. C., Roc. Soe. Erp. B i d Md,29,268 (1930). (10) Maurois. A., "The Life ofsir Alexander Fluning? E. P. Dutton, New York, 1959, p. 125. (11) &her, B., and Fox, R. C., 'The Soemlogy of Sdezlce," The h e P m .NB. Ymk 1962. P

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(12) Wdhun,J.H.,and O'Boum,ES.."T~~hiigthbP~~~it tfSsiiii; M ~ m i l h , New York, 1965.

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