LETTER TO TH E ED I TOR
Re fle ct ion s on t h e m a in e pist e m ologica l cu r r e n t s r e ga r din g h e a lt h
scie n ce s
J V a sc Br a s. 2 0 0 7 ;6 ( 4 ) :4 0 2 - 5 .
Technological pr ogr ess in science is r em ar kable and undeniable, especially regarding t he healt h area. Financial invest m ent s in t his sect or have exponent ially gr ow n in r elat ion t o t he ear ly 20t h cent ury, and ev en w ork- up and t her apeut ic m et hods available t o healt h professionals ar e based on scient ific st at em ent s, t heories and law s.1 How ever , such t echnological increm ent was only possible
t hanks t o deep philosophical reflect ions t hroughout t im e and t hat w er e oft en conflict ing.2 , 3 I t
becom es relevant t o know t he m ain philosophical concept ions and t heir influence on t he evolut ion of healt h sciences, w hich allow s a bet t er under st anding of t heir dynam ism and fallibilit y.1 - 3
Philosophy can be defined as t he st udy charact erized by hum an int ent ion of w idening it s know ledge about t he r ealit y, in or der t o com pr ehend it as a w hole, w het her in m at erialized and/ or im aginar y real " Being" , w het her in t he definit ion of inst rum ent s able t o cor r obor at e a t hought , a fundam ent , a law or a principle. A digest , defined as a det ailed descript ion about fact s, bet w een philosophy correlat ions and t he scient ific m et hod, allow s us t o see t hat t hroughout t im e t he philosophical t hinking w as est ablished in different cur r ent s w it h peculiar definit ions and foundat ions, w hich, how ever , as a com m on sense, har m onize and com plet e such differences.2 , 4 , 5
Despit e t he line of t hought called logical posit ivism or logical em pir icism having been init ially creat ed by m at hem at icians and physicist s in Aust r ia ar ound 1920, Com t e w as it s m ain charact er. Com t e's posit ivism was based on t he principles of logic and m at hem at ics as foundat ions for know ledge or confir m at ion of hypot heses, since t hey est ablished r ules independent of exper ience. For Com t e, even gener al st at em ent s and scient ific law s could be obt ained based on obser vat ion or induct ion of a phenom enon, w het her it w as nat ur al and/ or experim ent al.2 , 6
How ever, posit ivist s faced sever al cr it icism s t hat w er e based on t he fact t hat every scient ific observat ion is im m er sed in t heories, such as, for exam ple, m easur ing t em perat ure w it h a m ercury t herm om et er, w hose pr inciple is t hat all m et als dilat e w hen t heir t em perat ure incr eases. And, due t o t he possibilit y t hat obser vat ions could incor por at e fallible t heor ies, it w ould not be possible t o consider t hem as safe sour ces t o build know ledge, neit her as a solid foundat ion for scient ific developm ent .
Validit y of induct ive reasoning w as also quest ioned, since induct ion is not a deduct ive ar gum ent and, t her efor e, is not logically valid. The m ain exam ple is t hat befor e t he first confir m at ion of t he exist ence of black sw ans, it w as believed t hat all sw ans w er e w hit e. I nduct ion could not , t her efor e, be j ust ified neit her by logic, nor by exper ience.2 Even t he pr act ice of scient ific evidence st resses t hat one should be car eful about conclusions based on per sonal experience, independent ly of pr ofessional populat ion and of t he individual's scient ific know ledge.1
achieving t r ut h about t he scient ific m et hod and gener al know ledge w it hout only involving
induct ion, w hich could be possible using as pr inciple t hat obser vat ions could only be used t o r efut e ( deny, reprove) gener al st at em ent s, not being possible t o evolve any know ledge w hose t heories w er e not open t o cr it icism and r efut at ion. Popper also defined t hat st at em ent s pot ent ially able t o cont radict a law or t heor y w ould be called pot ent ial falsifiers and t hat t he gr oup of such falsifiers w ould ser ve as a par am et er for t he em pir ical cont ent of t he t heory: t he m or e t he t heor y
" prohibit ed" t hem ( t hey are now ident ified as exclusion crit eria) , t he m or e it w ould t ell us about t he w or ld.2 , 7 Therefore, scient ific cr it icism is cr ucial for scient ific pr ogr ess.1 , 8 , 9
Finally, Popper claim ed t hat t he level of cor r obor at ion ( accept ance) increased w hen w e m oved from older t o m or e r ecent t heor ies and researches in t he follow ing m anner : sear ch for know ledge
st art ed w it h t he form ulat ion of hypot heses t hat aim ed at solving pr oblem s and t hat should r esist t he m ost rigid t est s as possible. I n case t hey did not resist , hypot heses w ould be r efut ed and r eplaced by ot her s, w hich w ould also be t est ed and so fort h.2 , 7 , 1 0 Hence t he im por t ance of cont inuit y in research, of det ailed m et hod descript ion, of st at ist ical analysis of result s and st udy publicat ion.2 , 7 , 1 1 How ever , it is im port ant t o under st and t hat , ev en aft er t hey are confir m ed,
hypot heses should be accept ed as t em porary solut ions for a given problem and t hat , sim ilarly, t heir r efut at ion w ill alw ays be conj ect ur al, since t here m ight have been an error in obser vat ion, experim ent or even a r andom error.2 - 4 , 9
Popper was crit icized by t he cur r ent called " t he new philosophy of science," represent ed by Kuhn, Lakat os and Feyerabend, w ho claim ed: " st at em ent s and t est s are im pr egnat ed w it h t heor ies; w e usually t est com plex t heoret ical syst em s, and not isolat ed hypot heses."2 , 4 , 1 2 , 1 3 For Thom as Kuhn, in Th e St r u ct u r e of Scien t ific Rev olu t ion s( 1962) , t he m er e observat ion of a given t heor y
incom pat ibilit y or r efut at ion w ould not j ust ify it s abandonm ent by t he researcher; on t he cont r ar y, he should analyze m at ur ely t he crit icism s and unconfirm ed result s t o save his t heory, only
j ust ifying such at t it ude w hen faced w it h t he follow ing fact s: significant discrepancy bet w een
predict ed and expect ed, accum ulat ion of anom alies found or t hat prevent ed it s pract ical applicat ion and t hat r esist ed for a long t im e, even aft er t est r epet it ion or change. Confr ont ed w it h such
phenom ena, t he researcher w ould have a scient ific crisis, w hich, in it s t urn, w ould fost er sear ch for a new paradigm .1 , 2 , 4 , 7 , 8 , 1 2 Also accor ding t o Kuhn, t her e is a change in paradigm in t hose
" scient ific revolut ions," and alt hough t he w or ld does not change aft er a change in paradigm , t he scient ist begins t o see and w ork in a differ ent w or ld."2 , 1 2
On t he ot her hand, for I m r e Lakat os ( 1922- 1974) it w ould alw ays be possible t o pr event one
t heory from being refut ed, as long as changes w er e m ade only in auxiliar y hypot heses, m aint aining it s core int act , w hich is act ually one of t he char act er ist ics of a line of research.1 , 2 For Lakat os, t he hist ory of science show s t hat t heor ies are not abandoned, ev en aft er being refut ed. Sim ilar ly t o Thom as Kuhn, Lakat os claim ed t hat a scient ific t heory can be r ehabilit at ed at any t im e, as long as som e researchers keep w or king on it .2 , 4 , 1 0 , 1 3 This is one of t he r easons t o experience t hr oughout t im e scient ific r easoning and conduct s t hat have alr eady been used in past t im es. How ever , it is essent ial t o crit ically analyze t he j ust ificat ion of t rying again som et hing t hat could not be explained and/ or approved before, consider ing w het her t here is plausibilit y in t he pr oposal brought back t o life.1 , 2 , 4 , 9
But it was Feyerabend w ho dared t o challenge t he logic of scient ific harm ony. Wit h great
exclusiveness, he cr eat ed t he anar chic concept ion of science by claim ing t hat it does not have it s ow n m et hod, a rigid rule, neit her it is a r at ional act ivit y, but an anarchic ent repreneurship in w hich any previously proposed m et hodological rule, including rules of logic, w er e at som e t im e violat ed by scient ist s, r epr esent ing a cr ucial st age t o m ake science pr ogr ess.2 , 4 Nevert heless, at t he sam e t im e he w as cont r adict ing Kuhn, saying t hat he could not see a place for t he obj ect ive cr it er ia of assessm ent s, he corroborat ed his predecessors by st at ing t hat one should not abandon a t heor y w hen faced w it h refut at ions.2 , 4 , 1 2 , 1 3 Despit e Feyerabend's appar ent r adicalism , t he hist ory of
against current bioethical principles are no longer accepted by everyone involved in scientific progress.8,9
Finally, sociology of science also stood out, focusing on the great influence existing between social factors and scientific activity, according to which it is common that evaluations, awards and
publications of papers and researches in relevant scientific journals are determined not only by their scientific contents, but also by social factors. The "victory" of these works would then be a result of a dispute or negotiation between scientists, institutions or even countries.2,4
The statements of sociology of knowledge were also quite criticized by different sectors, since it is hard to accept that the success of science is only based on negotiations and social and political interests. In addition, it is known that one of the ways to achieve fame, professional success and funds is by producing methodologically correct studies.1,2,14 But such information obligatorily refers us to a deep reflection on this theme.
It can then be perceived that the different philosophical currents about the scientific method
allowed a wide space for a mature and highly constructive debate of science itself and that changes in paradigms have always occurred and will always occur. Not investing or escaping from scientific rigor implies abdicating the possibility of correcting errors, thus abdicating the true spirit of science itself.
Rica r do Cost a - V a l
Titular member, SBACV. President, SBACV-MG, 2008-2009. MSc. and PhD, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil. Professor, Graduation: Academic Master's in Health Sciences, Universidade Vale do Rio Verde (UninCor), Betim, MG, Brazil, and Instituto de Previd€ncia dos Servidores do Estado de Minas Gerais (IPSEMG), Belo Horizonte, MG,
Brazil.Address: Rua Boa Esperan•a, 341/101, Bairro Carmo, CEP 30310-730 – Belo Horizonte, MG, Brazil.Telephone: (31) 9972.6066. E-mail: ricardocostaval@hotmail.com
M a r ia Cr ist in a M a r qu e s
Nursing Administrative Manager, Hospital Galba Ortopƒdico, Funda•„o Hospitalar do Estado de Minas Gerais (FHEMIG), Belo Horizonte, MG, Brazil. Graduate student, Auditing in Health Systems, Faculdade S„o Camilo, Belo Horizonte, MG, Brazil. Coordinating Nurse of the International,
Multicenter Clinical Trial (Phase 3) "F7 Trauma-1711" under responsibility of Novo Nordisk…, unit
Hospital de Pronto Socorro Jo„o XXIII, FHEMIG, Belo Horizonte, MG, Brazil.
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Gewandsznajder F. O mƒtodo nas ci€ncias naturais e sociais. S„o Paulo: Pioneira; 1999. p. 65-84.
3. Tanaka OY, Melo C. Reflex‰es sobre a avalia•„o em servi•os de saŠde e a ado•„o das abordagens qualitativa e quantitativa. In: Bosi MLM, Mercado FJ, organizadores. Pesquisa qualitativa de servi•os de saŠde.Rio de Janeiro: Vozes; 2004. p. 121-36.
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publicacoes-1/ apost ilas/ espir it o_posit ivo_com t e.pdf.Acessado: 28/ 07/ 2007.
7. Papineau D. Met hodology: t he elem ent s of philosophy of science. I n: Gr ayling AC, edit or . Philosophy: a guide t hrough t he subj ect . London: Oxford Universit y; 2000. p. 123- 80.
8. Cost a- Val R. A im inent e m udança de paradigm a na relação ent r e a indúst ria far m acêut ica e a m edicina. J Vasc Br as. 2007; 6: 104- 6.
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11. Yoshida WB. A nossa pr odução cient ífica invisível. J Vasc Br as. 2005; 4: 113.
12. Assis JEP. Kuhn e as ciências sociais [ disser t ação] . São Paulo: FFLCH- USP; 1991.
13. Lakat os I . Crit icism of t he pr oof- analysis by count er exam ples w hich ar e global but not local: t he pr oblem of r igour . I n: Lakat os I . Proofs and refut at ions: t he logic of m at hem at ical discover y. London: Cam br idge Univer sit y; 1976. p. 42- 50.
14. Dr um ond JGF. Os vint e anos da FAPEMI G. J Est ado de Minas. Seção Opinião, m ar ço 2006, p. 11.
