Chr. Tønsberg nye Forlag

15/03/2026

https://turtagro.no/foredrag-med-knut-ihlen-tonsberg-150-ar-med-norsk-klatresport-22-august-2026/

25/02/2026

02/03/2024

https://www.vpg.no/Fra-forlag-til-fjell/393366/

Fra forlag til fjell Glimt fra Tønsberg-slekta er en personlig beretning med vekt på Tønsberg-familiens virksomhet i den norske fjellheimen. Det starter med Nils Chr. Tønsbergs forlagsinnsats på 1800-tallet og fortsetter med fire generasjoner Henning Tøn…

17/02/2024

Jotunheimens mest populære klatrerute er Heftyerenna på Store Skagastølstind. I boka "Fra forlag til fjell" får du historien om Heftyerenna. Det var ikke Johannes Heftye som klatret først. Han ble med egne ord "heist opp".

13/02/2024

Ny bok lanseres 15. mars 2024:

11/07/2021

På tide å finne Slingsby og Sulheims bortgjemte buemerker

Av Knut I. Tønsberg

Fjellhelten William Cecil Slingsby (1849-1929) satte spor etter seg på flere måter. Midt i det som kanskje er vår villeste fjellnatur, traktene langs Utladalens vestside, hogget han og Torger Stenersen Sulheim (1840-1925) inn årstallet 1877 og sine initialer i en stein. Det hadde vært morsomt om denne steinen ble funnet og de gamle buemerker og årstallet fotografert. Men hvem kan finne nøyaktig hvor den ligger?

En setning i en gammel DnT-årbok forteller at inskripsjonen ble funnet engang i årene før krigen. Den var hogget inn i en mosegrodd stein. Og når steinen var mosegrodd den gang, er den nok ikke mindre mosegrodd nå. Så å finne steinen med mesternes merker, vil neppe bli lett. Men litt har vi å hjelpe oss med.

Det som het Høyfjellskommisjonen arbeidet fra 1921 med å gå opp almenningsgrensene i Jotunheimen. Per Anker, titulert som dommer i innholdsfortegnelsen, skrev artikkelen «I Høyfjellskommisjonens fotspor» i Turistforeningens årbok 1948, fra side 133 og utover. Han går grundig til verks og forteller blant annet at Den Gudbrandsdalske almenningskommisjon arbeidet med grensene i årene 1874-1882. Den satte opp spesielle varder med «med innhogd krone». Denne kommisjonen arbeidet imidlertid bare med skogkledde deler av almenningene og Høyfjellskommisjonen fra 1921 tok fatt der den gamle kommisjonen sluttet. Anker beskriver på en morsom måte hvor almenningsgrensene går gjennom fjellområdene i Jotunheimen, med interessante bemerkninger av historisk og geografisk interesse. Ikke minst om forhistorien til «Hytta på Bandet» og grensene i Midtmaradalen. Så kommer på side 138 i årboken en aldri så liten perle av opplysning:

«Fra Midtmaradalen over til Skoddedalen. På høyderyggen mellom disse dalene kikker vi på en mosegrodd stein, hvor Slingsby og Torger Sulheim har risset inn W. C. S., T. T. S. 1877. Slingsby var ofte her i traktene ved Utladalen, dette jutulhogget som har skilt en neve med sprikende fingrer, Hurrungadn, fra resten av Jotunheimkroppen».

Skal vi finne steinen bør vi antakelig lete langs grensen mellom Vettis eiendom og statsalmenningen, for det var rimeligvis langs grensene kommisjonen i første rekke beveget seg. «Slik som kommisjonen har trukket almenningsgrensen, ligger bare den ytterste del av Midtmaradalen på privat eiendom, «Midtmaradalsvand» hører statsallmenningen til». Men kommisjonen fortsatte sin vandring oppover, inn i Skoddedalen og over til Maradalen, i følge Anker. Det kan med andre ord være duket for å børste mose av steiner fra den lille vannpytten nedenfor Midtmaradalen, rett før elva stuper ut i fossene ned mot Utla, og oppover langs det som ser ut som en kant i terrenget på avstand. Anker skriver steinen med inskripsjoner ble funnet «på høyderyggen» mellom Midtmaradalen og Skoddedalen. Så her har vi et bra utgangspunkt for å starte letingen.

Hva kan vi så lese av Slingsbys tekst i boka ´Norway The Northern Playground´?

Slingsby passerte Skoddedalen og gikk over i Midtmaradalen på sin berømmelige tur med Knut Lykken og Emanuel Mohn i 1876 da Slingsby klatret opp på Store Skagastølstind som den første. Tilbake gikk de samme vei og ned til Vormelid fra Maradalen. Slingsby beskriver i sin bok hvordan Emanuel Mohn og han kom tilbake senere samme sommer og utforsket terrenget fra Stølsmaradalsetra rundt det vi idag kaller Snørestø mellom Stølsmaradalen og Midtmaradalen, ned til pytten i Midtmaradalen og utover mot Utla. Beretningen kan tyde på at de forsøkte seg rundt Snørestø før de kom seg over. Det forteller mye om de tos krefter og iver etter å utforske terrenget. Å ta seg fram på vestsiden av Utla er ikke bare slitsomt, men fordrer den ene kraftanstrengelsen etter den andre med flere hundremeters stigninger opp og ned, storsteinet ur og den reneste urskog. Fra Snørestø og ned til pytten i Midtmaradalen er det ikke mindre enn 400 meters høydeforskjell. Fra pytten går det en slags sti ned det stupbratte terrenget mot Vormeli. Kyrkjestigen. Slingsby og Mohn lette seg frem her – og Slingsby beskriver turen i maleriske vendinger.

Slingsby synes å ha forelsket seg i denne delen av Utladalen, hvor avstanden mellom den østlige og den vestlige dalsideveggen er på det trangeste. Det som nå kalles Styggegjelet. Nord for dette gjelet slipper Kyrkjestigen seg ned fra Midtmaradalen. Og hit kom han altså tilbake året etter, i 1877.

Beretningen om turen i 1877, er ikke mindre malerisk – og like dramatisk som den første. I 1877 skulle Slingsby på bjørnejakt med Torger Sulheim. Det startet med at Anfinn Vetti fulgte ham ned til Utla fra Friken på østsiden. Sulheim møtte dem med hest nede ved elva. Over Utla får Slingsby en tøff ridetur, tøffere enn nødvendig. Sulheim ledet hesten med Slingsby gjennom frådende vannmasser for å se hvor tøff engelskmannen var – og lo godt når han fortalte at elven løp roligere litt lengre ned. Slingsby besto Sulheims test, selvfølgelig. Han hadde utmerket seg som rytter allerede i ungdommen (jmf Snoad, 2011). Deres lange vennskap tyder også på at de må ha satt pris på hverandres humor. Sulheim og Slingsby fortsatte med å jakte bjørn, og det måtte de gjøre til fots. De fulgte bjørnespor oppover det som heter Rolandstigen mot Skoddedalen. Bjørnesporene var ferske, og etterhvert ble de ledet bort mot toppen av Kyrkjestigen der Slingsby og Mohn året før hadde kommet ned. Sulheim ville gjerne opp og se inn i Midtmaradalen, se hvordan Store Skagastølstind tar seg ut derfra. Han og Slingsby klatrer til topps på det som må ha vært en slag pillar eller pinakkel, ´kyrkjespiret´i Kyrkjestigen, rett nedenfor Midtmaradalen. Slingsby som klatrer klødde selvfølgelig i fingrene etter å bestige denne – og Sulheim lokkes altså med av en mulig utsikt til Store Skagastølstind.

Slingsbys skildringer av Utladalens villskap og skjønnhet når ingen grenser: «The place perfectly fascinated me, and I found it difficult to tear myself away from so wild, so beautiful, and so indescribable a scene, where order and chaos, savage grandeur and quiet beauty were so strangely and so harmoniously blended, and Sulheim and I both agreed that we must see more of this some time in the future».

Slingsbys bok «Norway the Northern Playground» anbefales. 1877-turen er beskrevet på sidene 178-182.

Fra toppen av ´kyrkjespiret´ så ikke Sulheim og Slingsby Store Skagastølstind. De måtte med andre ord ha gått høyere opp i nedre del av Midtmaradalen for å få et glimt av Storen. Men det står ikke noe om at de virkelig gjorde det. Bare at Sulheim ønsket å se Storen og at klatringen opp på pinakkelen i så henseende var nytteløs. Hvem vet, kanskje de fortsatte et stykke til oppover etterpå? Et sted har de i hvertfall satt seg ned og risset inn sine initialer. De kan ha benyttet Slingsbys isøks som det står i boka at han hadde med seg. Det han ikke skriver noe om, er at de vitterlig hugget inn sine buemerker og årstall, på dette bortgjemte sted. Det ble en ytterst eksklusiv og overraskende hilsen til dem som kom etter.

Erling Eggum i Slingsbystiftelsen lover ut middag og overnatting til dem som finner inskripsjonen; på legendariske Klingenberg hotell på Årdalstangen. Der er det som kjent en stor Slingsbysamling og Slingsby selv var fast gjest der fra begynnelsen av 1870-tallet. En annen i Slingsbystiftelsen er Rigmor Solem i Statens naturoppsyn. Hun har hovedansvar for nasjonalparken og Utladalen landskapsvernområde og mener inskripsjonen ikke må fargelegges med maling når den blir funnet. Et kritt sammen med koster for å renske vekk mosen ligger derfor klar i hytta i Stølsmaradalen slik at inskripsjonen kan fotograferes.

Til å hjelpe oss i letingen kan vi legge sammen opplysningene fra Ankers artikkel fra 1948 og Slingsbys beretning fra boka som kom ut i 1904. Jan Schwarzott nevner også i boka si fra 1998 i en fotnote på side 302: «Slingsby og Sulheim forlot ikke åstedet uten spor: «W. C. S. & T. T. S. 1877» står det risset inn i berget». Inskripsjonen er stavet så godt som likt det som står i DnT-årboken fra 1948.

Schwarzott oversatte Slingsbys bok og Schwarzotts fotnote er knyttet til teksten som omhandler turen i 1877. Schwarzott har i den oversatte teksten tatt med en setning som ikke er hentet direkte fra Slingsbys første-utgave. Etter at de to hadde klatre ned igjen fra ´Kyrkjetårnet´ sto de to «og glodde dumt inn i en fjellvegg der utsikten etter våre beregninger skulle ha vært», utsikten er utsikten mot Storen. Dette i følge Schwarzotts oversettelse, side 98. I følge fotnoten til Schwarzott kan man kanskje forstå det slik at det er her inskripsjonen står «risset inn i berget».

Før jeg leter ved pinakkelen vil jeg imidlertid lete i terrenget fra pytten nederst i Midtmaradalen langs det som etter hvert blir ´høyderyggen mellom disse dalene´, mellom Midtmaradalen og Skoddedalen´, etter Ankers anvisning. Det er tross alt Anker som forteller at han har sett inskripsjonen på en ´mosegrodd stein´.

Den som finner inskripsjonen bør sjekke nøye om ikke Sulheim kan ha risset inn T S S, istedet for T T S. Det ville passet bedre.

Ett sted ligger steinen med sin historiske inskripsjon og kanskje nettopp utsikt mot Store Skagastølstind; samt kanskje Centraltind og Kjerringa, to topper som Sulheim senere var blant førstebestigerne av.

Det likner ikke Slingsby å ha nektet Sulheim å få et glimt av Storen og hans «highway to the top», Slingsbybreen, før de returnerte ned Kyrkjestigen i 1877. De var tross alt veldig nære. Og intet sted kunne vært bedre for Slingsby å sette sitt bortgjemte buemerke enn nettopp et sted med slik utsikt der han selv, Knut Lykken og Emanuel Mohn hadde passert 21. juli 1876 på vei til og fra Storen.

Og kanskje var det da de satt og risset i steinen at Sulheim fikk lysten på å bli førstemann på noen av de andre toppene. Slingsby ville på sin side ha mer av Utladalen. I 1881 kom han tilbake midtvinters. Bjørnejakt var igjen det erklærte mål, men Slingsby ville også ta seg frem langs bunnen av Utladalen fra Vormeli til Vetti. Det ble en annen og ikke mindre spennende tur med Halvar Halvarsen og Thorgeir Sulheim. Slingsby skriver Thorgeir, med h og i. Den andre skrivemåten, mellomnavnet Stenersen og Sulheims leveår, som jeg har nevnt innledningsvis, er hentet fra Schwarzotts bok.

Referanser:

DnTs årbok 1948

Slingsby, Wm Cecil; Norway: The Northern Playground ( Edinburgh David Douglas, 1904 i opptrykk av David Durkin, Swami Kailash Publications)

Slingsby, Wm. Cecil; Mountaineering in Norway, paper read for the members of Burnley Literary and Sientific Club, Burnley Express and Advertiser on Saturday, 9th February 1884. Transcript by John Snoad

Snoad, John: William Cecil Slingsby, YRC Journal (Yorkshire Ramblers´ Club) issue 12, series 13, winter 2011

Slingsby, Wm. Cecil, utvidet og oversatt av Schwarzott, Jan: Norge den nordlige arena, Grøndahl, Oslo 1998.

Om gården Eide i Skjolden som Steinar Torgerson Sulheim kjøpte i 1851: https:// www. allkunne.no /framside/fylkesleksikon-sogn-og-fjordane/historie-i-sogn-og-fjordane/historie/storgarden-eide-i-skjolden/1901/79248/

Om Klingenberg hotell og Slingsby: https:// www. allkunne. no/ framside/fylkesleksikon-sogn-og-fjordane/samfunn/industri-naring-og-bedrifter/klingenberg-hotel//1900/82340/

22/01/2021

Ett av de mange crux-punktene på Haute Route

Haute Route i Alpene passerer egentlig ikke over noen fjelltopper, med ett unntak. Pigne de Arolla i Sveits, 3798 m.o.h. To populære ruter fra hyttene Chanrion og Dix passer noen titalls meter under toppen av Pigne de Arolla. Toppvarden blir en liten avstikker fra turløypa. Men fra toppen av turløypa er det en meget spesiell nedfart til hytta som ligger som et ørnerede på en egg ut fra fjellsiden, Cabane de Vignette. Det er fra Vignette man starter på den eventyrlige etappen over tre pass til Zermatt. Ikke uten grunn er hytta ettertraktet. Den er et fantastisk sted, med eventyrlige og krevende turer på ruta mellom Chamonix og Zermatt.

Fra toppen av Pigne de Arolla er fjellsiden ned mot Vignette uten faste holdepunkter å navigere etter. I den gamle guideboka til Peter Cliff, som jeg brukte første gang, står rett og slett høyden angitt hvor man skal ta ut til siden for å finne den rette passasjen ned til hytta. Det gjelder med andre ord å justere høydemåleren før man passerer toppunktet på ruta. Så slipper man seg ned fjellsiden til angitt høyde, svinger til siden og tar seg noen hundre meter vannrett mot venstre/øst. Der stuper terrenget under et hengebratt breparti og ned til en smal egg som leder bort til hytta. Å finne veien ned her i tåke og whiteout, er ikke lett. Det gjelder ikke å skjære ut til siden for tidlig, og heller ikke for sent. Det gir en underlig følelse å skifte kurs og ta seg horisontalt mot en skråning som etter hvert blir brattere og brattere - og til slutt veldig bratt. Men dette er utrolig morsomt i godvær!

Så hva gjorde man med usikre værvarsler? Mine erfaringer er fra årene rundt 2010. Fra Chanrion unngår man toppen av Pigne de Arolla ved å gå via Ottema-breen til Vignett. Fra Dix kan man gå ned til landsbyen Arolla, som man i ettertid kanskje kan si at den omtalte gruppen kunne ha gjort. Fra Vignett til Zermatt skal du ha klarvær for å gå drømmeturen over de tre passene. Men man kan gå fra Vignett, og fra landsbyen Arolla til Cabane de Bertol og fra Bertol er det enklere å komme videre til Zermatt, enn det er fra Vignett. Rett og slett fordi du fra Bertol kommer ned på rett side av Col de Valpeline som er vanskelig å passere i tåke. Mine erfaringer er over ti år gamle. Mye skjer med breene. Til Bertol-hytta har de sikkert måttet forlenge jernstigene opp fra breen der skiene plasseres - og passasjene som er omtalt over kan ha endret seg.

Første gang jeg kom på disse trakter kom John Anderson og jeg fra Chanrion på ski i begynnelsen av mai. Vi hadde passert Plateau de Coloir dagen før. Ingen av oss hadde gått Haute Route før - og vi brukte boka til Cliff. Vi hadde sjansen til å nå toppen av Pigne de Arolla, vi var noen titalls høydemeter unna. Men på nabotoppen hang en liten sky - på en ellers solfylt dag. Jeg rushet på - ikke snakk om å ta avstikkeren til toppen! Det sto klinkende klart for meg at cruxet - passasjen til siden måtte nås i klarvær og en sky kunne være en for mye. Den lille skyen ble imidlertid hengende over nabotoppen i ro, og vi hadde flott vær til sent på kveld. Til toppen av Pigne de Arolla kom jeg først noen år senere med Fredrik Wiese og Rune Wendelboe. Etter råd fra Chamonix-guiden Michel Schneider gikk vi fra Arolla til Vignette, og satt igjen sekkene før vi tok oss opp det bratte henget og videre til toppen av Pigne de Arolla og ned igjen. Michel Schneider var et utrolig nyttig bekjentskap. Mer om det senere.
https://www.outsideonline.com/2329041/chamonix-zermatt-alps-haute-route-disaster?utm_source=facebook&utm_campaign=facebookpost&utm_medium=social&fbclid=IwAR1k23aC8k2Dnz9sUb32v-oUvxrMSnZiAKQRGWvIERydK2XbngWy69a-oqU

Thousands of people flock to the Alps each year to ski tour high-elevation routes, spending comfortable nights in a string of huts that serve wine and hot meals. This spring, a group of experienced skiers and their guide were trapped in a storm overnight on an exposed saddle. By morning, nearly all....

13/11/2020

Av og til kommer man over gamle Tønsbergtrykk på antikvariatene. Her Troldtinderne i Romsdalen, nesten så man kan tegne inn klatreruta opp Trollryggen i kanten av Trollveggen. Antakelig håndkolorert, men bare langs dalbunnen!

31/01/2020

INDUCTION AND DEDUCTION

Knut Ihlen Tønsberg
December 2019
Faculty of Pedagogy
University of Oslo

Scientific reasoning has been called either inductive or deductive up through history. I will argue in this paper that induction and deduction hardly can be isolated. My point is thinking that leads to discoveries and new knowledge consists of both inductive and deductive processes. However a third term could be used according to how induction is defined. Progress in the scientific contexts of both discovery and justification rely on a back and forth process.

I will start with a brief introduction to induction and deduction with some illustrative, historical examples. I will not elaborate too much on the different definitions of induction and deduction more than strictly necessary for the purpose of this paper.

Aristoteles (384-322 BC) introduced the terms induction and deduction as two opposite processes. He illustrated his points with syllogisms, arguments with two premises like, All humans are mortal, Socrates is a human, ergo Socrates is mortal, a deductive inference.

INDUCTION

Induction is commonly looked upon as inferences from the individual relationships to the general propositions. The inductive conclusions are reached by a step by step process from individual particulars, observations or experiences to more comprehensive general laws or propositions, statements, theories, t-terms, constructs, hypotheses or representations. 1
All the particular swans we have seen have been white, ergo all swans are white.

Putting together single pieces like a jigsaw puzzel could be a metaphor for the simple, enumerative induction. Piece by piece are fitted together until a picture eventually will occur when the jigsaw is assembled. But most often is something more needed to bring us from single parts to a whole picture.

Tycho Brahe (1546-1601) looked at the planet Mars and wrote down its positions at various times over many years. He tried to describe its orbit through the universe from these particular observations. Each and every observation linked together should describe a path. The process linking these particular observations together, step by step could be called an inductive process of reasoning. But it surely was not like any jigsaw puzzel. Brahe tried to calculate but did not find the matching pattern. The Mars’ orbit became a mystery for him. I shall come back to what blocked the inductive ladder for Tycho Brahe, and what eventually cleared it for his assistant in Praha.

There are some problems with induction: all particulars might not be possible to check, like the swans. And therefore the conclusion might be wrong. Only one black swan may pull the carpet under the statement all swans are white. This illustrates an inductive general problem: the general conclusion are not absolute certain. This brings us to the so called Problem of Induction.

THE PROBLEM OF INDUCTION

The question is whether it is always possible to reach a conclusion, a general statement, only by logical unambiguously reasoning from the particulars? Induction requires conclusions that, apart for the simple enumerative inductions, “go beyond the scope of the supporting premises”.(Gimbel 2011, p 43). Thus induction is ampliative. That means a conclusion, a general proposition is not reached only by logical, unambiguously reasoning. Something more is needed, and furthermore the conclusions are not arrived at with absolute certainty.

The reeknown empiricist, David Hume (1711-1776), elaborated on this. He presented an everyday example of consequences as he said were drawn by the mind:

“The bread, which I formerly eat, nourished me ; (…) but does it follow, that other breads must also nourish me at another time (...) There is required a medium, which may enable the mind to draw such an inference, if indeed it be drawn by reasoning and argument. What that medium is, I must confess, passes my comprehension ; and it is incumbent on those to produce it, who assert that it really exists, and is the origin of all our conclusions concerning matter of fact» (Hume 1927 s. 33).

No one doubt the bread will nourish us tomorrow, or the Sun will rise again, neither Hume did. The point is we cannot produce the logical arguments that will exclude all other possibilities and unforeseen instances. Hume wrote the same about causality, cause and effect. His point is that we draw these inductive inferences in our mind – strictly speaking without the necessary reasoning, logic and arguments that could entitle us to draw an inference with absolute certainty. Thus he dismissed causality.

Reasoning about the future is an inductive inference. It is typically not possible so say with 100 per cent certainty what will happen tomorrow. But it is not difficult to draw useful conclusions about breads nourishment without all of Humes necessary logical steps. It was worse to find Mars orbit. The little extra proved hard to find. Something was blocking the way for Brahe – he did not reach any conclusion. His orbits deviated no matter how many times he checked his calculations or wherever in the universe he tried to place the center of the orbit circle.

We do also have instances when induction leads to not only one, but more than one general assessment. Induction is underdetermind. That means there could be more than one general statement covering the same particular observations. An example: Both wave-theory of light and matter theory of light are needed to explain all observed properties of light.

So induction is associated with a lot of difficulties, both theoretically and. In a way deduction is somewhat simpler.

DEDUCTION THE ALL OR NOTHING AFFAIR

Deduction is the other way round, the opposite of induction. Deduction is defined as reasoning from the general to the particular, step by indubitable step. Like the syllogism about Socrates mentioned earlier. Deduction follows a logical process – by the way, all the way. The conclusion does not contain information you do not find in the premises. If the deduction is valid, claiming the premise and denying the conclusion will be a contradiction.

Deductive correctness known as validity is an all-or-nothing affair, logically perfect and strictly accountable.

Deduction may in accordance with this be looked upon as evidence, evidence that is based on the assumption of a given premise which with logical necessity will bring you to a certain conclusion. A general statement is checked by its concrete examples. Hypotheses and theories are tested, by deduction, against single observations. Thus deduction could be to draw the consequences of axioms, definitions and already proven sentences, like in mathematics.

All swans are white, is a general statement that can be tested and corroborated again and again against the particular swans we see. And if a black swan turns up, as it has, the statement is falsified. When you know Mars’ orbit, you may foresee the planets position tomorrow and check if your theory is correct. You may also check if other planets’ movements through space follows the same pattern – both through deduction. But you must reach a general assessment first. This raises some interesting questions concerning scientific discoveries.

Throughout history scientists have discussed whether induction or deduction should be declared as the scientific process of reasoning. I will not go deeply into the history of philosophy of science, but a few sentences may shed some light on the issue of scientific discoveries.

HISTORY

Francis Bacon (1561-1626) was important for the scientific thinking although he did not contribute with any concrete discoveries of importance himself. Bacon believed, and expressed in writing, how the rational must go forward by building on induction. In the centuries following Bacon's praise of induction, philosophers of science struggled with the later called the Problem of Induction. As mentioned, to clarify whether one really could reach general hypothesi’ by inductive methods alone, remained highly problematic. 2

The so called positivists, starting with August Comte (1798-1842), turned the coin. Comte classified the sciences and pointed out that they were interconnected. Further on that sciences should be constructed with logical conclusions, step by step, ideally as mathematics and physics 3, and thus namely by deduction.

It might not be surprising that deduction was a rising star as the scientific method. Especially not when highly significant, scientific discoveries and achievements were paving the way for industrialization and economic growth in a scale never seen before. The indubitable step by step processes and certainty reached by deduction was much more useful than the ampliative and more uncertain induction.

But not all followed suit. The logical empiricists in the so called «Vienna Circle» took the stage in the 1930s and tried to turn the coin again. They said induction was the scientific process, only to be categorically opposed by the Viennese Karl R. Popper (1902-1994). He claimed solving the Problem of induction by saying science is to be synonymous with falsification through deductive reasoning called the hypothetical deductive account, HD-account.

The HD-account was to be the method up to the 1960s. Although Comte had aimed for a universal scientific method, the HD-account was looked upon as first and foremost the tool for natural sciences, where the quantitative methods were used and very successful.

Today a bipedal approach with both quantitative and qualitative methods, are more commonly used. This has not always been the case. Eyebrows were for example raised when the HD-account was used to analyze a literary drama like Henrik Ibsens’ Peer Gynt in the 1970s4. But no literary agent has put the question raised in this paper so explicit as a reenown crime author.

SHERLOCK HOLMES AND THE SCIENCE OF DEDUCTION

In the 1800s and beyond, famous crime writers, like Arthur Conan Doyle, were concerned that their heroes were using scientific methods to solve the crime mysteries. And scientific methods were called deductive no matter, as we shall see, they would better fit the definition of induction.

Their heroes put together small pieces of information in a way that eventually formed a pattern and a picture of what had happened. A lot of loose pieces were put together as a jigsaw puzzle into a complete picture that revealed the criminal. The conclusions of Sherlock Holmes should be rational and logical, and thereby explicit scientific. So deduction had to be his tool. «Detection is, or ought to be, an exact science» (Doyle 1877, p. 93).

Chapter two of the first Sherlock Holms story, «A Study in Scarlet», is called «The Science of Deduction». Likewise the first chapter in the story «The Sign of The Four». (Doyle, 1877).

The detective is piecing together bits of information that at first seems quite irrelevant for the audience, but in the end forms a picture of the crime and a surprising solution. Neither the detective’s good friend dr Watson nor the readers would call it elementary, but quite spectacular and only in the end reasonable and logical.

The conclusions clearly reveal more information than the premises. The method Sherlock Holms demonstrate is explicit ampliative: «... observation shows me that you have been to the Wigmore Street Post-office this morning, but deduction lets me know that when there you despatched a telegram» (Doyle 1877, p 96). This is not what we have called deduction. Holms cannot be 100 percent sure, but it is a good guess.

Furthermore, Holms is reasoning about cause and effect, causality. «The only point in the case which deserved mention was the curious analytical reasoning from effects to causes by which I succeeded in unraveling it» (Doyle 1877, p. 94). Hume would have pointed his finger and said it was more like creative guesswork than exact science the detective was demonstrating. The hypotheses and solutions are found with inferences and ampliative add on.

Mr. Sherlock Holmes’ method is more in line with (ampliative) induction, or inference to the best explanation, as we shall see later is called abduction.

Nevertheless the deductive part is often explicit in crime novels; but usually not before the last chapter when the detective has formed a hypothesis and makes the villain reveal himself, when the hero tests the hypothesis or theory of who the villain is.

But the processes described in these crime novels is not a bad picture of how, also in scientific contexts, bit by bit of concrete information is put into context and little by little an image is formed and a theory of the actual conditions is created. It may also show how induction and deduction are used as a back and forth process. This was also the case when Brahe and his assistant tried to find Mars’ orbit.

Kepler describes the orbit of Mars

Norwood Russel Hanson (1924-1967) is writing about Johannes Kepler (1571-1630) in his book Patterns of Discovery published in 1958. Kepler became Tycho Brahes assistant in Praha right before Brahe died. He inherited Brahe’s protocols with all the particular observations, time and positions of where the planet Mars had been through many years. Brahe had tried in vain to describe the orbit of the planet. No matter where he and later Kepler placed a center of a circular orbit in the universe, the calculations wouldn’t ad up. Neither the Sun nor the Earth was the center, and apparently nowhere else. Kepler kept on calculating and calculating for ten more years after Brahes death. Over and over again did he count, looking for the error he was sure must have been hiding somewhere in his calculations. Indeed it was no easy reasoning, no easy inductive ladder to climb from the particular observations to the general construct. No probability measures could either help him – the deviation was always too big.

Brahe and Keplers work fits the definition of induction in one way: they were reasoning from particulars towards a general description. But in a way did they also work deductively. They tried to find a center Mars is circulating around. They chose some hypotheses. They put a center at different positions in the universe and checked if they got a match with the observations – working-hypothesis that were tested by their calculations; and failed. They did not find any simple curve that matched the observations no matter how many times they did the calculations searching for the error, and no matter where they placed the center. I took Kepler 10 years before he managed to look outside the box.

Every astronomer and astrologer up through history had said planets moved in circular orbits. That was their divine pattern. Kepler was theoryladen, says Hanson. Not until he freed himself from the circle and tried an oval, did he succeed. The step from an oval to an elipse was short. An elipse is moving around two centers. The Sun is only one of them.

Hanson is reflecting on the way Kepler worked. He had written a detailed account of all he did, step by step. “When he (Kepler) at last found the elipse his work as a creative thinker was virtually finished. Any mathematician could then deduce further consequences not included in Tycho’s list. It required no genius to take Kepler’s idea and try it for other planets» (Hanson 1972 s. 84).

The leap from the particular observations to the eliptical curve was not a straight forward procedure – it was a leap across a knowledge gap. It could be an example of the inductive ampliativity. But philosophers disagree. The Norwegian professor of philosophy, Arne Naess, (a profounder of the H-D account) said Kepler worked deductively5. Hanson says no, and wrote some clear arguments against the H-D account:

«By the time a law has been fixed into an H-D system, real original physical thinking is over. The pedestrian process of deducing observation statements from hypotheses comes only after the physicist sees that the hypothesis will at least explain the initial data requiring explanation. The H-D account is helpful only when discussing the argument of a finished research report, or for understanding how the experimentalist, or the engineer develops the theoretical physicists’ hypotheses; the analysis leaves undiscussed the reasoning which often points to the first tentative proposals of laws» (Hanson 1972 ss. 70-71).

We will leave the question whether Brahe and Kepler worked inductively or deductively – or used both methods - for a while. Instead, what could be said of the reasoning which points to the first tentative proposals of a general statement, theory or law? In short where do the hypotheses come from?

AMPLIATIVITY IN THE FORM OF A LEAP

We have seen how piecing together information demands something extra in addition to logical reasoning and inferences: The ampliativity that may form part of the inductiv ladder from particulars to the general statement. It could also be described as a less specific leap or jump:

John Dewey (1859-1952) said «the sources of suggestions (…) Clearly (are) past experience and prior knowledge» (Dewey 1910 s. 12). But not alone. The steps in human inquiry includes
a suggestion. «Suggestion is the very heart of inference; it involves going from what is present to something absent, it involves a leap, a jump, the propriety of which cannot be absolutely warranted in advance, no matter what precautions be taken» (Dewey 1910 s. 75).

This fits with Brahe and Kepler. Their past experiences and prior knowledge concerning circular (devine) orbits lead them astray. Hanson uses this as the example to illustrate his term theoryladen. And the leap, the jump Kepler finally did could not be absolutely warranted in advance, no matter what precautions he might take. This was new ground and illustrates the ampliativity. Kepler had to add something extra in addition to the information about, and inferences from the positions, or particularities, observed. He had to add some working-hypotheses first about an oval then about an elipse. That is how he in practice dealt with the problem of induction. Reasoning is a back and forth process we may describe as a dialectic procedure.

John Dewey (1859-1952) says this about reasoning back and forth to reach new ideas:

«But reasoning (or ratiocination)seems to be peculiarly adapted to express what the older writers called the «notional» or «dialectic» process of developing the meaning of a given idea» (Dewey 1910 s. 76).

I will come back to Dewey. Let us first dig a bit deeper into what the little extra add on is about.

IN THE FORM OF PROBABILITY

The ampliativity could be, and fairly often is a statistical probability. Inductive arguments «admit degrees of strenght depending upon the amount of support the premises furnish for the conclusion»6. Even Francis Bacon said induction which proceeds by simple enumeration leads to uncertain conclusions.

The truth ideal was replaced by probability – when epistemologists switched from deduction to induction.7 «Probability is not an invention made for the sport of gamblers (...) it is the essential form of every judgement concerning the future and the representative of truth for any case where absolute truth cannot be obtained», Hans Reichenbach (1891-1953) wrote.8

Reichenback was a Vienna Circle associate from Berlin. Probability had for long been a useful instrument that brings us from the particulars to the general. But Hans Reichenbach and the Vienna Circle did not get many followers concerning induction. Quite contrary, the deductive approach took the stage and the H-D account was looked upon as the scientific method, at least in the post-war period. This was the hard sciences’ method. But an open question remained about where the hypotheses used in the H-D account come from.

WHERE DOES THE HYPOTHESES COME FROM?

This is clearly the forgotten question among the H-D account followers. With the Brahe/Kepler history as an example, Hanson raised the question and said the issue is not theory-using, but theory finding (Hanson 1972 s. 3). Popper points to psychology and does not offer much help: “there is no such thing as a logical method of having new ideas”9.

Without the ampliativ leap, Hanson writes off (enumerative) induction: ”There is no inductive method which could lead to the fundamental concepts of physics…in error are those theorists who believe that theory comes inductively from experience” (Hanson 1972 s. 119).

John Dewey separated our thinking processes in two contexts, one which is about the discovery of new ideas and one which is about the justification, and he links one to induction and the other to deduction:

“When pains are taken to make each aspect of the movement toward building up the idea is known as inductive discovery (induction for short); the movement toward developing, applying, and testing, as deductive proof (deduction for short)” (Dewey 1910 p 81).

Hans Reichenback later used the two terms context of discovery for the process leading to a theory or hypothesis and context of justification for the process to confirm it. But while Dewey had linked induction and deduction to each one of the two contexts, Reichenback were somewhat unclear.

«We may add the remark that the distinction of the context of justification from the context of discovery is not restricted to inductive thinking alone. The same distinction applies to deductive operations of thought» (Reichenbach 1957 s. 383-4).

In this added remark Reichenbach blurs the distinction between his two terms context of discovery and context of justification. It is an added remark. It has not been integrated into the rest of the text where the two terms are used, nor has it found its way to the register. The pages where it is written are not listed together with the other pages where the two terms are used. He may have added the remark as some kind of answer to Popper at a late stage in preparing the manuscript for publication. It is most likely written at the end of the production process. The terms context of discovery and context of justification were launched with a twist.

It makes sense to talk about a dialectical process within both context of discovery and within context of justification. As we have seen with the Brahe/Kepler example the step by step reasoning from particulars, the induction, is mixed with working hypotheses that are tested and eliminated, deduction, on the way to the general hypotheses – first the oval and then the eliptical orbit.

However Dewey does not say explicitly that we have the dialectical processes between induction and deduction within each contexts. He links induction and deduction to each one of them. On the other hand, as earlier mentioned, does he say we have “a «dialectic» process of developing the meaning of a given idea”.

It makes sense to look upon this dialectic process as a back and forth process between induction and deduction – which is necessary both within context of discovery and within context of justification.

Reichenbach had somehow tied himself to the mast by pointing to induction as the scientific method to conceive new ideas. Nevertheless his added remark indicates he had some doubts – shall we say blocked by his theoryladen attitude towards induction and deduction? So what about Hanson?

Hanson not only writes off the inductive process, he also reject the deductive with some clear statements:

«Physicists do not start from hypotheses; they start from data. By the time a law has been fixed into an H-D system, really original physical thinking is over. The pedestrian process of deducing observation statements from hypotheses comes only after the physicist sees that the hypothesis will at least explain the initial data requiring explanation. (...) the analysis leaves undiscussed the reasoning which often points to the first tentative proposals of laws» (Hanson 1972 ss. 70-71).

Hanson elaborate on the relation between particular observations and theories. He turns the relationship up-side-down:

«A theory is not pieced together from observed phenomena; it is rather what makes it possible to observe phenomena as being of a certain sort, and as related to other phenomena. Theories put phenomena into systems. They are built up ‘in reverse’ – retroductively. A theory is a cluster of conclusions in search of a premise. From the observed properties of phenomena the physicist reasons towards a keystone idea from which the properties are explicable as a matter of course. The physicist seeks not a set of possible objects, but a set of possible explanations» (Hanson 1972 s. 90). This could well describe a part of Dewey’s dialectical process. When the scientist has arrived at some working hypothesis and is looking upon the particular observations to see if they fit in.

Hanson elaborate further on his example, Kepler was hindered by how he perceived, looked upon the observation figures with a circle in mind. So what was it that finely brought the answer?

«Kepler did not begin with the hypothesis that Mars’ orbit was eliptical and then deduce statements confirmed by Brahe’s observations. These later observations were given, and they set the problem – they were Johannes Kepler’s starting point. He struggled back from these, first to the hypothesis of the elliptical orbit. Few detailed accounts have been given of philosophers of science of Kepler’s achievements, although his discovery of Mars’ orbit is physical thinking at its best. These philosopher of physics should not neglect what Peirce calls the finest retroduction ever made» (Hanson 1972 s. 72).

ABDUCTION

Hanson gives reference to Charles Sanders Peirce (1839-1914), the term retroduction and also mentions his use of the word abduction.

Pierce studied Aristoteles and said the Greek philosopher had described a third term abduction together with induction and deduction. He said «every single item of scientific theory which stands established today has been due to abduction» (Peirce 1893-1913 s. 216-7)

Pierce changed his positions over the years. In his last lecture at Harvard in 1903 did he say this about abduction:

“The abductive suggestion comes to us like a flash. It is an act insight, although of extremely fallible insight. (...) If we were to subject this subconscious process to logical analysis we should find that it terminated in what that analysis would represent as an abductive inference resting on the result of a similar process which a similar logical analysis would represent to be terminated by a similar abductive inference, and so on ad infinitum (…) so this process of forming the perceptual judgment, because it is subconscious and so not amenable to logical criticism, does not have to make separate acts of inference but performs its act in one continuous process» (Peirce 1893-1913 s. 227).

Pierce says the ideas come as a flash, Dewey says by a leap; it is the same. The flash/leap materialize as the ampliative part of induction or abduction.

Abduction is today usually called an Inference to the Best Explanation. Not surprising is abduction by some looked upon as some sort of induction (Norton 2005 s. 16).

Igor Douven writing for the Stanford Encyclopedia of Philosophy says so about abduction relative to induction: « … the best way to distinguish between induction and abduction is this: both are ampliative, meaning that the conclusion goes beyond what is (logically) contained in the premises (which is why they are non-necessary inferences), but in abduction there is an implicit or explicit appeal to explanatory considerations, whereas in induction there is not; in induction, there is only an appeal to observed frequencies or statistics.» (Douven 2011). Induction is according to this linked to probability, abduction to a more vague definition.

Pierce was of the opinion that Apelicon (died 84BC) who had brought Aristoteles’ books to Athen, had made an error when rewriting the texts. Peirce thought the text, which is about an inductive inference, didn’t make sense so he rewrote it himself. The tittle of the text, the Greek word , is by Pierce translated with abduction.

So there should be solid reason to link induction and abduction together – also when referring to Aristoteles. Whether abduction is a part of induction – or the other way round may be a matter of definition.

There does not seem to be a way around the described leap, the little extra in addition to logical reasoning and inferences to bring us scientific discoveries and new knowledge. We may talk about induction or abduction. The ampliativity is crucial – and it is needed both within the contexts of discovery and justification.

There is also a clear observation to be made: as we have seen, deduction is quite often used as synonymous with strictly unambiguous reasoned and logical inferences – no matter whether they go from the particulars to general statements, as in the crime novels, or the other way round. While induction and abduction are comcerned with a psychological flash or leap.

To sum up, scientific reasoning has been called either inductive or deductive throughout history – with varying definitions. Abduction and induction are two terms with much in common, namely the ampliativity. I do not think induction and deduction in practice can be isolated. My point is that thinking which leads to discoveries and new knowledge consists of both inductive and deductive processes. Progress in scientific contexts of both discovery and justification relies on a back and forth, dialectical process.

There seems to be an analogy to how we think; both slow and fast thinking. The induction/deduction processes resembles our two types of cognition: one intuitive, analogous to induction/abduction and one logical analogous to deduction10. Further analogies have been of the utmost importance for many years. David Hume wrote, with two words in capital letters:

«ALL our reasoning concerning matter of fact are founded on a species of ANALOGY, which leads us to expect from any cause the same events, which we have observed to result from similar causes» (Hume 1964, p. 85).

Perhaps this might be a starting point for another paper.

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