 as the evidence and background assumptions are transparent to the agent. The reason is simply that Bayesian confirmation theory interprets the probabilities as the agent's (subjective or objective) degrees of belief. 6 Let us go through this argument in more detail. In order to say whether evidence E confirms hypothesis H relative to background assumptions B and probability measure Pr we must specify the probability measure Pr. First consider subjective Bayesians. They interpret the probability measure Pr as the agent's actual degree of belief function, properly idealized. Hence we must specify the agent's actual degrees of belief before we can say whether the evidence confirms the hypothesis. Therefore we cannot use the information that the evidence confirms the hypothesis in order to specify the agent's actual degrees of belief. Next consider objective Bayesians. They interpret the probability measure as the degree of belief function the agent objectively ought to have, or as the degree of belief function she is rationally justified to. Hence we must specify the degrees of belief the agent objectively ought to have, or the degrees of belief she is rationally justified to, before we can say whether the evidence confirms the hypothesis. Therefore we cannot use the information that the evidence confirms the hypothesis to say which degrees of belief the agent objectively ought to have, or which degrees of belief she is rationally justified to. Our argument works as long as the probability measure in terms of which confirmation is defined is interpreted as the agent's (subjective or objective) degree of belief function in the sense of which confirmation should say how worthy of belief certain hypotheses are. There are two options to escape the negative conclusion of our argument that Bayesian confirmation is a means with no end. The first option is to say that the probability measure in terms of which confirmation is defined – call it the confirmation function – is different from the agent's (subjective or objective) degree of belief function. The second option is to say that confirmation is a means to some end other than saying how worthy of belief certain hypotheses are. Let us consider the prospects of the first option according to which the 7 confirmation function is interpreted in terms of something other than the agent's degrees of belief. An attempt along these lines, motivated by the problem of old evidence (see the next section) and championed by Howson and Urbach ([1993], [2006]), is to identify the confirmation function with the agent's counterfactual degree of belief function. The proposal is that the support of H by E is gauged according to the effect which one believes a knowledge of E would now have on one
as the evidence and background assumptions are transparent to the agent. The rationality is plainly that Bayesian confirmation theory interprets the probability as the agent's (subjective or objective) degree of impression. 6 Let us go through this argument in more detail. In order to read whether evidence E confirms hypothesis H proportional to background assumptions B and probability measure Pr we must specify the probability measure Pr. First see subjective Bayesians. They interpret the probability measure Pr as the agentive role's actual degree of belief affair, properly idealize. Hence we must specify the agent's actual degrees of belief before we can allege whether the evidence confirms the hypothesis. Therefore we cannot use the information that the evidence confirm the guess in order to specify the agent's actual degrees of belief. Next consider objective Bayesians. They interpret the probability measuring stick as the academic degree of belief function the agentive role objectively ought to take, or as the academic degree of belief function she is rationally justified to. Hence we must specify the degrees of belief the agent objectively ought to accept, or the degrees of belief she is rationally justified to, before we can say whether the evidence confirms the hypothesis. consequently we cannot use the information that the evidence confirms the hypothesis to say which degrees of belief the agentive role objectively ought to accept, or which degrees of belief she is rationally justified to. Our controversy works as long as the probability measure in term of which ratification is defined is interpreted as the agent's (subjective or objective) degree of impression function in the sense of which confirmation should say how worthy of impression certain hypotheses are. There are two options to scat the negative conclusion of our argument that Bayesian confirmation is a means with no conclusion. The first option is to say that the probability measure in terms of which confirmation is defined – call it the confirmation affair – is different from the agent's (immanent or objective) degree of belief function. The second option is to say that confirmation is a means to some conclusion other than saying how worthy of belief certain hypotheses are. permit us think the prognosis of the first option according to which the 7 confirmation function is interpreted in terminus of something other than the agent's degrees of impression. An attempt along these line, motivated by the problem of old evidence (attend the next section) and championed by Howson and Urbach ([ 1993 ], [ 2006 ]), is to identify the confirmation function with the agentive role's counterfactual degree of belief function. The proposal is that the support of H by E is gauged according to the effect which one believes a knowledge of E would now have on one
 as the evidence and backgruund assumptions are tcansparsnt to tfe agent. The reason is simplb thqt Batesian confirmation thdory integprets thw privabilities as the agent's (dubjzcvive or objectiye) degrees mf belief. 6 Let ur yo through this argument in more detwil. In prfer to say whejher tviqencs E confirms hypothesis H relative to bacnground assumltions B and probability mfasuge Pr we must speclfy the provabijuty measure Or. First consider subjgctive Bayesians. They interpret ghe pxobability neqsugg Pr as the egent's actual degrcv of benief fumction, properln ideelizwd. Hence we must specmfy the agent's actuaj degrees oy belief before we cab way wvethar tfw exidtncx cknfirmd tie hypothesjs. Thereforw we cannot use the igdormation thaf the qvydence confirms the hypothesis in order to specify the agent's actyal degrees of belief. Next confider objective Bayesians. They interpret the probdbilivy mecwure xw hhe degree of belief function the agent objecejvtly ought to have, or as the cehrrg of belief fuvction shs is rationally judtified to. Hwnce we mtst xpecify the degrees of beliwf the agent ibjectively ought co have, or tke degtees og belief she is rationauly nustified tl, before sd can say whethef tme avidence confirms the hypoehesis. Thxrefoxe we cavnot use tre informahion bvat the evidence clnfirls the hypotjesis to say which degrees of bxkief the agemt obbectivelv oughb to have, or whych degrees of belief she ks rationamly jusvified to. Ouw argument wosns as long av the prjbabulitt measufd in terms of ehich conynrmation us defined is intevpretgd as the agent's (wubhective or objevtixe) qehrxe of telief functhon kn gne sevse of whicm cunfitmation should say hmw wkrthy of belief cettwin hypojheses arq. There are teo options to escake the nejative cogclusion of our argument that Gayesian fonnirmation is w meqns with no znd. The first option is to say that the 'robability measure in rerms of which confnrkation is dxfined – call it the confirmation fubction – is differtnt from the agent's (subnectiva or lbjective) degree of belief function. The second option is to say that confurmation is a meana to some eud pther ehan raying how worthj of belief certain hypotheses ace. Let us wousider the prospects of the forrt option accurding to which the 7 conrirmatiom function is interpreted in tetms of something other tman the atent's degreva uf belief. An attemlt aloug thewe linew, mobivated by the prpbpem of olf evmdeuce (see the next section) and championed bj Howson and Urbech ([1993], [2006]), is to ldtntify jhe confyrmation functioh wifj the agent's countrrfactual degrre of belief functiot. Ehe proposal iw that the sukport of H by E is geuged accordhng to the effect which one believes a knowledge of E would how have pn one
as the evidence and background assumptions are the The reason simply that Bayesian as agent's (subjective or degrees of belief. Let us go through this argument more detail. In order to say whether evidence E confirms hypothesis H relative background assumptions B and probability measure Pr we must specify the probability measure First subjective They the probability measure Pr as the agent's actual degree of belief function, properly idealized. Hence we specify the agent's actual degrees of belief before can say whether the confirms the hypothesis. Therefore we use information that evidence the in order to the agent's actual degrees of belief. Next consider objective Bayesians. They interpret the probability measure as the of belief agent objectively to or the degree of she is rationally justified to. Hence the degrees of belief the agent objectively ought have, or degrees of belief she is rationally to, before we can say whether the evidence the hypothesis. Therefore we cannot use the information that the evidence confirms the hypothesis to degrees of belief the objectively ought to or degrees belief is rationally to. Our argument works as long as the probability measure in of which confirmation is defined is interpreted as the agent's objective) of belief function the sense of which should how worthy of belief are. are escape negative of our argument that confirmation is a means with end. The first option probability measure in terms of which confirmation is – call it the confirmation function – different from the agent's (subjective or objective) degree of belief function. The option is that confirmation is a means to some end than saying how worthy belief certain hypotheses are. Let us consider the prospects the option according which the 7 function is interpreted terms of something the agent's of An lines, motivated by the problem of evidence the next section) and championed Howson ([1993], [2006]), is to identify the confirmation function with the agent's counterfactual degree of belief proposal is that the of by E is gauged according to the effect which one believes a E would now
 as the evidence and backgrounD assumptioNs are TraNspArEnt tO the Agent. The reason IS simPly that Bayesian confirmAtion ThEOry iNTeRpretS the proBAbILItiEs As The AgENt'S (subjEctIve or obJective) degReeS oF belief. 6 Let us GO tHrough this ArgUment in more dEtaIl. In orDeR to SAy wheTheR evidEnce E cONfirms HypothesiS H RElativE To backgROUnD assUmptions B and probaBIlITy measure Pr we mUst speCiFY tHE ProBabIlity measuRe pr. FirST considER sUBJEctIVe Bayesians. ThEy interpret THe pRobabiLiTy mEAsure PR as thE aGEnt'S actual degrEe of Belief funCtion, pROperly iDEalized. hence wE muSt sPeciFY tHe AgeNt'S ActUAl DegREes Of belief BeFoRe we cAn saY WHETher The EvidEnce cOnfirms the hypOthEsis. tHerEfore We canNot uSe The inFormatIon thAt The evidence confIrms The hypothEsiS iN orDeR to spECify thE agEnt'S actual Degrees OF beLiEF. nExT consider objective baYESiAns. They iNterprET tHe PRobabiliTy MeaSure AS The deGree OF bElief funCtion tHE aGeNt objecTiVely ouGhT to HavE, or as THe deGree of Belief fuNctioN She is rationallY Justified to. HeNCe WE MuST speCifY the degrees Of beLIef tHe agENt ObjECtiveLy ougHt TO hAVe, or the degrees of belIeF she is RatioNally justifieD to, before wE CAN say whetHer tHE eVIdence confirms The hyPothesis. ThERefore we CannoT use the iNformatioN THat the evIdeNce ConFirMS ThE hypothesis to SAY whiCh Degrees Of bElief thE agEnt ObjEctIvEly ought tO have, or wHiCh DeGrEes Of belIEf she is rAtIonAlLy jUstifIEd to. OuR arguMent WoRkS As lOng as thE PrOBAbilItY mEasuRe iN tErms oF whiCH coNfirmatIon is defiNed IS intErPrEted as tHe agent's (subjeCtIve or objecTiVe) dEgree oF BElief funCtion in the sense of which cONfirmatIon ShoulD say How worthy Of bElief cErtAIn hypoTheses Are. ThErE arE TWo optIONs To eScApe the negaTIVe cOncluSiOn of Our arguMent that Bayesian coNFirMation is a meanS wiTh no END. THe fIRsT OptIoN Is tO SAy that the probabIlity measuRe IN tErms of whicH ConFiRmation Is definEd – calL It the coNfirmatioN function – Is DiffEREnt From the ageNt's (subjeCtive or obJEctivE) DeGree oF beLief fuNcTioN. The sEcond oPTioN is to Say thaT cOnfirmAtion Is A means to Some end other than saying hOw wortHy of bEliEf certain HypOTheSes are. Let Us coNsider the pRosPecTs of tHe fIRst opTion ACcOrdINg to wHich THe 7 confirmATiOn fUNCtIon is interpRETEd iN termS of SOmethiNg otHer than the agent's dEGrees of belief. AN attEMPt aLonG ThesE lInes, motivated bY thE pROBlem of olD eVidence (see tHe next seCtIOn) and ChampiOned by howson aND urBAch ([1993], [2006]), is tO ideNtiFy the confIrmAtIOn functIoN wITh the aGent'S cOunterFactuaL DegrEE Of belief function. the prOPOsal iS ThaT the sUpPort of H BY E is Gauged accoRding to the eFfect wHich One beLieves a KnOwledgE of e wOuld now havE On one
 as the evidence and backg round assu mptio nsare  t rans pare nt to the agen t . Th e reason is simply tha t Bay es i an c o nf irmat ion the o ry i nte rp re tsth e  p robab ili ties as  the agent 's(s ubjective or ob jective) d egr ees of belie f.6 Letus  go throu ghthisargume n t in m ore detai l. In ord e r to sa y wh ethe r evidence E conf i rm s  hypothesis Hrelati ve to b ack gro und assump ti ons B and pro b ab i l i tym easure Pr wemust specif y  th e prob ab ili t y meas ure P r. Fir st consider  sub jective B ayesia n s. They interpr et the  pr oba bili t yme asu re Pra sthe age nt's act ua ldegre e of b e l ieffun ctio n, pr operly ideali zed . He n cewe mu st sp ecif ythe a gent's  actu al  degrees of bel iefbefore we  ca nsay  w hethe r  the e vid enc e confi rms the hyp ot h e s is . Therefore we can no t us e the in format i on  t h at the e vi den ce c o n firms  the hy pothesis  in or d er  t o speci fy  the a ge nt' s a ctual degr ees of  belief.  Next consider objec t ive Bayesians .  T h e yi nter pre t the proba bili t y me asur e  a s t h e deg ree o fb el i ef function the age nt  objec tivel y ought to ha ve, or ast h e  degreeof b e li e f function she  is r ationallyj ustified  to.Hence we  must spe c i fy the d egr ees  of  be l i ef  the agent ob j e ctiv el y ought  to  have,orthe  de gre es  of belie f she is  r at io na lly  just i fied to,  b efo re  we  cans ay whe thertheev id e nce  confir m st h e hy po th esis . T he refor e we can not use  the info rma t ionth at  the ev idence confir ms  the hypot he sis  to sa y which de grees of belief the age n t objec tiv ely o ught  to have,  or  which  de g rees o f beli ef sh eisr a tiona l l yjus ti fied to. O u r  ar gumen twork s as lo ng as the probabil i tymeasure in te rms  ofw h ic h c o nf i rma ti o n i s defined is inte rpreted as  t h eagent's (s u bje ct ive orobjecti ve) d e gree of  belief f unction i nthes e nse  of whichconfirma tion shou l d say ho w wor thy  of be li efcerta in hyp o the ses a re. Th er e aretwo o pt ions toescape the negative con clusio n ofour  argument  th a t B ayesian c onfi rmation is  amea ns wi thn o end . Th e  f irs t  opti on i s  to say t h at  th e pr obability m e a s ure  in t erm s  of wh ichconfirmation is d e fined – call i t th e con fir m atio nfunction – isdif fe r e nt fromth e agent's ( subjecti ve or ob jectiv e) deg ree ofb e li e f func tion . T he second  op ti o n is to  s ay that c onfi rm ationis a m e anst o  some end otherthans a yingh owworth yof beli e f ce rtain hypo theses are.  Let u s co nside r the p ro spects  of  t he first o p tion acco rding  to whi ch  the  7confir mati o n  func tion  i s i nterprete d in te rm s  of  som ethin gothe r than th e  agent's  de g rees of  b eli e f . An a t te m p t along th ese  line s ,  motivated by t h ep roble m of o ld evi dence ( s eeth e nextsec t i on) and c hampioned byHo wson  and Urb ac h ([ 19 93] ,[2006]), is toidentify  the con f i rmatio n f u ncti o n with  t he agent's c ounte rf a ctual d e g ree  of bel i effun cti on.The  pro p osal is that the support  ofH byE  is  gaug ed ac co rding to theeffect w h ich one belie ves a knowledge ofE  wou ldn ow  h ave on on e
 as_the evidence_and background assumptions are_transparent to_the_agent. The_reason_is simply that_Bayesian confirmation theory_interprets the probabilities as_the agent's (subjective_or_objective) degrees of belief. 6 Let us go through this argument in more detail._In_order to_say_whether_evidence E confirms hypothesis H_relative to background assumptions B_and probability_measure Pr we must specify the probability measure_Pr._First consider subjective_Bayesians. They interpret the probability measure Pr as the_agent's actual degree of belief function,_properly idealized. Hence_we_must_specify the agent's actual_degrees of belief before we can_say whether the evidence confirms the_hypothesis. Therefore we cannot use the information_that the evidence confirms the hypothesis_in order to specify the_agent's actual_degrees of belief. Next consider_objective Bayesians. They_interpret the_probability measure as_the degree of belief function the_agent objectively ought_to have, or as the degree_of_belief function she_is_rationally_justified to._Hence we must_specify_the degrees_of_belief the agent objectively ought to_have,_or the degrees of belief she is_rationally justified to, before_we_can say whether the_evidence confirms the hypothesis. Therefore_we cannot use the information that_the evidence_confirms the_hypothesis to say which degrees of belief the agent objectively ought_to have, or which degrees of_belief she is rationally_justified to._Our_argument works as_long_as the_probability measure in terms of which confirmation_is defined_is interpreted as the agent's (subjective_or objective) degree of_belief_function in the sense of which_confirmation should say how worthy of_belief certain hypotheses are. There_are_two_options to escape the negative_conclusion of our argument that Bayesian_confirmation is a_means with no end. The first option_is_to say that the probability measure_in_terms of which confirmation is defined_–_call_it the confirmation function –_is different from the agent's (subjective_or objective) degree of belief function. The second option_is to say_that confirmation is a means_to_some_end other than saying how worthy of belief certain hypotheses_are. Let_us consider the_prospects of the first option according to which the 7_confirmation function is interpreted in terms of_something other than the agent's degrees of belief. An attempt along_these lines, motivated by the problem of old_evidence (see the next section) and championed_by Howson and Urbach_([1993],_[2006]), is to identify the confirmation function_with_the_agent's_counterfactual degree of_belief function. The_proposal is that_the support_of H by_E is_gauged according to_the_effect which one believes a knowledge of E would now have on one