poliomyelitisasavirusandthedevelopmentofavaccinefor
it;severaldiscoveriesthatservedtomakeopenheartsurgery
and coronaryartery bypassgraft surgerypossible; and the
understandingofourimmunesystemandwaystoovercome
rejection of transplanted organs.^136 The claim that animal
experimentationwasessentialinmakingthesediscoverieshas
beendeniedbysomeopponentsofexperimentation.^137 Ido
notintendtogointothecontroversyhere.Wehavejustseen
thatanyknowledgegainedfromanimalexperimentationhas
made at best a very small contribution to our increased
lifespan; itscontributiontoimproving thequalityoflife is
moredifficulttoestimate.Inamorefundamentalsense,the
controversy over the benefits derived from animal
experimentation is essentially unresolvable
, because even if valuable discoveries were made using
animals, we cannot say how successful medical research
wouldhavebeenifithadbeencompelled,fromtheoutset,to
develop alternative methods of investigation. Some
discoverieswouldprobablyhavebeendelayed,orperhapsnot
madeatall;butmanyfalseleadswouldalsonothavebeen
pursued, and it is possible that medicine would have
developedinaverydifferentandmoreefficaciousdirection,
emphasizing healthy living rather than cure.
Inanycase,theethicalquestionofthejustifiabilityofanimal
experimentationcannotbesettledbypointingtoitsbenefits
forus,nomatterhowpersuasivetheevidenceinfavorofsuch
benefitsmaybe.Theethicalprincipleofequalconsideration
ofinterestswillruleoutsomemeansofobtainingknowledge.
Thereisnothingsacredabouttherighttopursueknowledge.
Wealreadyacceptmanyrestrictionsonscientificenterprise.
We do not believe that scientists have a general right to
perform painful or lethal experiments on human beings