Reduction: For and AgainstReduction: For and AgainstChapter 7Chapter 7

Eric OberheimEric Oberheim

Sex & DeathSex & Death

BreakdownBreakdown

The Antireductionist ConsensusThe Antireductionist Consensus Reduction by degrees?Reduction by degrees? Are genes DNA sequences plus Are genes DNA sequences plus

contexts?contexts? The Reductionist AnticonsensusThe Reductionist Anticonsensus

Theory of reductionTheory of reduction

Translation of vocabulary of theory Translation of vocabulary of theory from old to new; bridge principlesfrom old to new; bridge principles

Hence old and new theories made Hence old and new theories made commensurable; classic -> molecularcommensurable; classic -> molecular

Bridge laws always possible Bridge laws always possible according to logical empiricists due to according to logical empiricists due to relation with observation and relation with observation and experimentexperiment

Objection to bridge lawsObjection to bridge laws

Kuhn & Feyerabend: no theory Kuhn & Feyerabend: no theory neutral observation vocabneutral observation vocab

Not applicable to geneticsNot applicable to genetics

The Antireductionist The Antireductionist consensusconsensus

One-to-many translationOne-to-many translatione.g. dominant allelee.g. dominant allele

Therefore Mendelian kinds may Therefore Mendelian kinds may have no distinctive molecular have no distinctive molecular propertyproperty

Thus two complementary and Thus two complementary and mutually illuminating theoriesmutually illuminating theories

Tree of explanatory Tree of explanatory dependencedependence

Theories don’t invent mechanismsTheories don’t invent mechanisms Tree is rooted in fundamental Tree is rooted in fundamental

physical processesphysical processes Discoveries in molecular biology Discoveries in molecular biology

shed light on classic geneticsshed light on classic genetics

Reduction by degrees?Reduction by degrees?

Multiple realisation Multiple realisation micro -> macromicro -> macro

Wave / Particle duality?Wave / Particle duality? The law of independent assortment The law of independent assortment

reduced to molecular levelreduced to molecular level

““Gory details”Gory details”

Kitcher - Gory details not important to Kitcher - Gory details not important to the explanatory power of Mendelian the explanatory power of Mendelian principlesprinciples

e.g. round peg square holee.g. round peg square hole No need for molecular explanation - too No need for molecular explanation - too

detaileddetailed Robust process explanationRobust process explanation Actual sequence explanation often Actual sequence explanation often

necessarynecessary

Contd...Contd...

Antireductionist many-many claim Antireductionist many-many claim that...that...

Old & new theories are integrated Old & new theories are integrated and causally explainedand causally explained

But methodologically and But methodologically and conceptually independentconceptually independent

Are genes DNA sequences Are genes DNA sequences plus context?plus context?

Hull: gene cannot be reduced just Hull: gene cannot be reduced just to DNAto DNA

Concrete structural object cannot Concrete structural object cannot be found; “position effects”be found; “position effects”

Broader molecular context Broader molecular context necessarynecessary

Neumann-HeldNeumann-Held

Gene as a process including Gene as a process including developmental matrixdevelopmental matrix

Impossible gene to DNA correlation Impossible gene to DNA correlation

The reductionist The reductionist Anticonsensus Anticonsensus

Says this reduction is not Says this reduction is not successfulsuccessful

Must be a relationMust be a relation This raises three important QsThis raises three important Qs

(i) more complex relationship?(i) more complex relationship?

(ii) ideological baggage(ii) ideological baggage

(iii) integrated Vs incorporated(iii) integrated Vs incorporated

Who knows?Who knows?

Waters and Schaffner argue in Waters and Schaffner argue in favour of theory reduction in favour of theory reduction in response to multiple realisationresponse to multiple realisation

Genes -phenotypic code or Genes -phenotypic code or difference makers?difference makers?

Transcription factors as distant Transcription factors as distant from gene, “coding sequence”from gene, “coding sequence”

What is a gene? Grrrrrr we What is a gene? Grrrrrr we still don’t know!still don’t know!

Gene does not name a unit of Gene does not name a unit of molecular bio. Shorthand for molecular bio. Shorthand for different units, a shifting tag.different units, a shifting tag.

Different biologists use different Different biologists use different meanings - exons Vs introns mRNA meanings - exons Vs introns mRNA etc.etc.

Morphogenetic fields Morphogenetic fields ploughedploughed

Unit of developing embryoUnit of developing embryo mosaic of 3-Dmosaic of 3-D strong intra but weak inter field strong intra but weak inter field

relationsrelations combination of gene, chemical combination of gene, chemical

milieu and environmentmilieu and environment develop mental output invariantdevelop mental output invariant

Flying in the face of Flying in the face of sciencescience

Stable outcomes e.g. four-winged Stable outcomes e.g. four-winged mutant ninja flies become two-winged mutant ninja flies become two-winged againagain

therefore developmental bio. Must be therefore developmental bio. Must be able to be reduced to molecular niveauable to be reduced to molecular niveau

poss explain genes on Macro-scaleposs explain genes on Macro-scale thus actual seq explanations do not thus actual seq explanations do not

undermine explanatory significanceundermine explanatory significance

And the winner is...And the winner is...

NOBODY NOBODY progress under both headingsprogress under both headings wishy-washywishy-washy not really independent theoriesnot really independent theories

Now you do that thing Now you do that thing where you knock on the where you knock on the

tabletable

ACHTUNG!ACHTUNG!

Bitte beachten Sie, dass fuer Bitte beachten Sie, dass fuer naechste Woche Kapitel 8 zu lesen naechste Woche Kapitel 8 zu lesen istist

Wer das nicht gelesen hat, darf Wer das nicht gelesen hat, darf nicht hereinkommennicht hereinkommen