 central. My goal in this paper is to track down these aberrant elements and show how the view works once they are eliminated. Let me begin with some puzzles for Lewis. They are not particularly deep: in fact, the correct solution to all three will probably jump out at you long before I have presented it. But they will help us begin to figure out what is really central to the modal realist's analysis of possibility and necessity. While the most general statement of this analysis is a bit complicated, its application in some simple cases is supposed to be quite straightforward. For example, we have the following analyses: (1) It is possible that some swans are blue↔df there is a Lewisworld such that some swans in it are blue. (2) It is possible that no swans are blue ↔df there is a Lewisworld such that no swans in it are blue. Here, a Lewis-world is a cosmos: according to Lewis's final analysis, an object none of whose parts bears any "analogically spatiotemporal" relation to anything disjoint from it, and which is not part of any other such object. The symbol '↔df' in (1) and (2) is supposed to indicate the giving of an analysis. Perhaps it may be rendered in English as 'For it to be the case that... is for it to be the case that... '. If we have any grip at all on what it means to give an analysis of something, we know that pφ ↔df ψq entails pNecessarily, φ iff ψq. If this is given up, it becomes entirely unclear how the meaning of (1) and (2) go beyond the meaning of the corresponding material biconditionals.1 So in particular, (1) entails (1′): 1Is pφ↔df ψq just equivalent to p(φ↔ ψ)q? There is pressure for Lewis to answer yes: it wouldn't be so exciting if one could analyse modality, counterfactuals, etc. in nonmodal terms but still had to take '↔df' as a primitive, manifestly non-extensional, operator. If one does answer yes, one will presumably have a pragmatic story to tell about why claims like 'For Socrates to be wise is for Socrates to be wise and not to be a round square' sound wrong. 1 (1′) Necessarily: it is possible
central. My goal in this paper is to track down these aberrant chemical element and picture how the view works once they are eliminated. get me begin with some puzzles for Lewis. They are not peculiarly deep: in fact, the correct solution to all three will probably startle out at you long before I have presented it. But they will help us get down to figure out what is really central to the modal realist's analysis of hypothesis and necessity. While the most general instruction of this analysis is a bit complicated, its lotion in some simple cases is supposed to be quite aboveboard. For example, we have the follow psychoanalysis: (1) It is possible that some swan are blue↔df there is a Lewisworld such that some swans in it are blue. (2) It is possible that no swan are blue ↔df there is a Lewisworld such that no swans in it are blue. Here, a Lewis - world is a cosmos: according to Lewis's final analysis, an object none of whose parts bears any " analogically spatiotemporal " relation to anything disjoint from it, and which is not part of any other such object. The symbol' ↔df' in (1) and (2) is supposed to indicate the giving of an psychoanalysis. possibly it may be rendered in English as' For it to be the case that... is for it to be the case that...'. If we get any grip at all on what it means to pass an analysis of something, we know that pφ ↔df ψq entails pNecessarily, φ iff ψq. If this is given up, it become entirely unclear how the meaning of (1) and (2) go beyond the meaning of the corresponding material biconditionals.1 So in finical, (1) entails (1′ ): 1Is pφ↔df ψq just equivalent to p(φ↔ ψ)q? There is pressure for Lewis to suffice yes: it wouldn't be so exciting if one could analyze mood, counterfactuals, etc. in nonmodal term but still had to take' ↔df' as a crude, manifestly non - extensional, operator. If one does answer yes, one will presumably take a pragmatic story to tell about why claims like' For Socrates to be knowing is for Socrates to be wise and not to be a round straight' sound incorrect. 1 (1′) Necessarily: it is potential
 cejtral. My goal in this paker is to track down theve abedrant eldments and show how the view wirks ince they are eliminatdd. Let me begin wuth wime puzzles for Lewis. Thsn are iot particularli deep: in fawt, the correct sulbtion to all three will probably jum[ out ay jou long beforg I hsde pdvstnted it. But they will help us befin to higure out what is really central to the lodap realist's analysid of possibulitr and necessigy. While the most genetal statement of this analysis ir a bnt complicajze, ihv applicatiin in some simple cases iv suppoxed to be quitc streighrforward. For example, xe have the followind analysev: (1) It is possible tyar somg swats afw buue↔sf tgere id a Lewisworls such that some swans in it ate vlue. (2) It is pkssiblq ehat no swans are blue ↔df there is a Lefissorld such that no swanw in it are blue. Here, a Lewis-wjrld is a cosmos: according to Lewis's final analyshs, an ubjtcb vinf of whose parts bears any "analogically spatijfekppral" relation bo anything disjoimt ftjm it, and whizh is ukt part of any other such ofject. The symbjl '↔dg' in (1) and (2) is supposed to ibdicate the yivung of an analysis. Perhaps it may be rrndered in English as 'Fur if to be the case thaf... is for it to be thv cave that... '. If we have any gryp at all on chat it oeanx to gyve an anapysis of something, we knlw thct pφ ↔gf ψq entaips pNecessarily, φ iff ψq. If this mx given up, ij bacokes entixely ukclear how the ieaning of (1) anb (2) go bevond tfe meaning of the correspondyng material tlconditionalv.1 So in [artuculqr, (1) entxkls (1′): 1Is pφ↔df ψq kust equinajent to p(φ↔ ψ)q? There is pvessute for Lewis to aurqer yes: it woulcn't be sl xxcitytg if one cogld xnauuse mudality, coukteffacyuals, etc. in nonmodan tedms but still had yo take '↔df' as a prymitive, manifrstly non-extensionwl, opxrator. If ome qoes answer yes, one will presujably havf a pragmatic seory to tell abobt why claims like 'For Socrates to be wiwe is for Socrates to be wise and not uo be a round squawe' sound frong. 1 (1′) Necessarily: ut is possible
central. My goal in this paper is down aberrant elements show how the eliminated. me begin with puzzles for Lewis. are not particularly deep: in fact, correct solution to all three will probably jump out at you long before have presented it. But they will help us begin to figure out what really to modal analysis of possibility and necessity. While the most general statement of this analysis is a bit its application in some simple cases is supposed be quite straightforward. For we have the following analyses: It possible that swans blue↔df is a Lewisworld that some swans in it are blue. (2) It is possible that no swans are blue ↔df is a that no in are Here, a Lewis-world cosmos: according to Lewis's final analysis, of whose parts bears any "analogically spatiotemporal" relation anything disjoint it, and which is not part any other such object. The symbol '↔df' in and (2) is supposed to indicate the giving of an analysis. Perhaps it may be English as 'For it be the case is it be case that... If we have any grip at all on what it means give an analysis of something, we know that pφ ↔df pNecessarily, iff ψq. If is given up, it entirely how the meaning of (2) beyond the material So in particular, (1) (1′): 1Is pφ↔df ψq just to p(φ↔ ψ)q? There answer yes: it wouldn't be so exciting if could analyse modality, counterfactuals, etc. in nonmodal but still had to take '↔df' as a primitive, manifestly non-extensional, operator. one does one will presumably have a pragmatic story to about why claims like Socrates to be wise is for Socrates to be and to be round square' sound 1 (1′) Necessarily: is possible
 central. My goal in this paper iS to track doWn theSe aBerRaNt elEmenTs and show how thE View Works once they are eliminAted. LEt ME begIN wIth soMe puzzlES fOR lewIs. thEy aRe NOt PartiCulArly deeP: in fact, the CorReCt solution to ALl Three will pRobAbly jump out aT yoU long bEfOre i Have pResEnted It. But tHEy will Help us begIn TO figurE Out what IS ReAlly Central to the modal REaLIst's analysis of PossibIlITy AND neCesSity. While tHe Most gENeral stATeMENT of THis analysis is A bit complicATed, Its appLiCatIOn in soMe simPlE CasEs is supposeD to bE quite strAightfORward. FoR Example, We have The FolLowiNG aNaLysEs: (1) iT is POsSibLE thAt some swAnS aRe bluE↔df tHERE Is a LEwiSworLd sucH that some swanS in It arE BluE. (2) It is PossiBle tHaT no swAns are Blue ↔dF tHere is a LewisworLd suCh that no sWanS iN it ArE blue. hEre, a LeWis-WorLd is a coSmos: accORdiNg TO lEwIs's final analysis, an ObJECt None of whOse parTS bEaRS any "analOgIcaLly sPATioteMporAL" rElation tO anythINg DiSjoint fRoM it, and WhIch Is nOt parT Of anY other Such objeCt. The SYmbol '↔df' in (1) and (2) is SUpposed to indiCAtE THe GIvinG of An analysis. PErhaPS it mAy be REnDerED in EnGlish As 'fOr IT to be the case that... is fOr It to be The caSe that... '. If we havE any grip at ALL On what it MeanS To GIve an analysis oF someThing, we knoW That pφ ↔df Ψq entAils pNecEssarily, φ IFF ψq. If thiS is GivEn uP, it BECoMes entirely unCLEar hOw The meanIng Of (1) and (2) go BeyOnd The MeaNiNg of the coRrespondInG mAtErIal BiconDItionals.1 so In pArTicUlar, (1) eNTails (1′): 1IS pφ↔df Ψq juSt EqUIvaLent to p(Φ↔ Ψ)q? tHEre iS pReSsurE foR LEwis tO ansWEr yEs: it wouLdn't be so eXciTIng iF oNe Could anAlyse modality, CoUnterfactuAlS, etC. in nonMODal terms But still had to take '↔df' as a pRImitive, ManIfestLy noN-extensioNal, OperatOr. IF One doeS answeR yes, oNe WilL PResumABLy HavE a Pragmatic sTORy tO tell AbOut wHy claimS like 'For Socrates to BE wiSe is for SocratEs tO be wISE aNd nOT tO Be a RoUNd sQUAre' sound wrong. 1 (1′) NeCessarily: iT iS PoSsible
 central. My goal in thispaper is t o tra ckdow nthes e ab errant element s  and  show how the view wor ks on ce they ar e eli minated .  L e t  me  b eg inwi t hsomepuz zles fo r Lewis. T hey  a re not parti c ul arly deep:  in  fact, the c orr ect so lu tio n  to a llthree  willp robabl y jump ou ta t youl ong bef o r eI ha ve presented it.B ut they will help  us be gi n  t o fig ure  out whatis  real l y centr a lt o the modal realist 's analysis ofpossib il ity and ne cessi ty .  Wh ile the mos t ge neral sta tement of this analysi s is a  bi t c ompl i ca te d,it s  ap p li cat i onin somesi mp le ca sesi s s uppo sed  tobe qu ite straightf orw ard. For  exam ple,we h av e the  follo wingan alyses: (1) Itis p ossible t hat  s ome  s wansa re blu e↔d f t here is  a Lewi s wor ld s u ch  that some swans i ni t  a re blue.  (2) I t  i sp ossibleth atno s w a ns ar e bl u e↔df ther e is a Le wi sworldsu ch tha tnoswa ns in it a re blu e. Here,  a Le w is-world is ac osmos: accord i ng t oL ewis 'sfinal analy sis, an o bjec t  n one of wh ose p ar t sb ears any "analogica ll y spat iotem poral" relati on to anyt h i n g disjoi nt f r om it, and whichis no t part ofa ny other  such  object.  The symb o l  '↔df' i n ( 1)and  (2 ) is  supposed toi n dica te  the gi vin g of an  an aly sis . P er haps it m ay be re nd er ed  i n E nglis h  as 'For  i t t obethe c a se tha t...is f or  i t  to  be the ca s e  tha t. ..  '.Ifwe  have  any gri p at al l on what  it mean sto  give a n analysis of  s omething,we  kn ow tha t pφ ↔df ψ q entails pNecessarily, φ iff ψ q.If th is i s given u p,it bec ome s  entir ely un clear  h owt h e mea n i ng  of  ( 1) and (2) g o b eyond  t he m eaningof the correspondi n g m aterial bicon dit iona l s .1  So in par ti c ula r ,  (1) entails (1 ′): 1Is pφ ↔d f  ψ q just equ i val en t to p (φ↔ ψ)q ? The r e is pr essure fo r Lewis t oansw e r  ye s: it woul dn't beso exciti n g ifo ne  coul d a nalyse  m oda lity,  count e rfa ctual s, etc .in non modal  t erms but  still had to take '↔df ' as a  prim iti ve, manif est l y n on-extens iona l, operato r.Ifone d oes answe r ye s ,one willpres u mably hav e  a  pr a g ma tic story t o t ell  abou t w h y clai ms l ike 'For Socrates to be wise isforS o cra tes to b ewise and not t o b ea round sq ua re' sound w rong. 1(1 ′ ) Nec essari ly: it  is pos s i bl e 
 central._My goal_in this paper is_to track_down_these aberrant_elements_and show how_the view works_once they are eliminated._Let me begin_with_some puzzles for Lewis. They are not particularly deep: in fact, the correct solution_to_all three_will_probably_jump out at you long_before I have presented it._But they_will help us begin to figure out what_is_really central to_the modal realist's analysis of possibility and necessity. While_the most general statement of this_analysis is a_bit_complicated,_its application in some_simple cases is supposed to be_quite straightforward. For example, we have_the following analyses: (1) It is possible_that some swans are blue↔df there_is a Lewisworld such that_some swans_in it are blue. (2)_It is possible_that no_swans are blue_↔df there is a Lewisworld such_that no swans_in it are blue. Here, a_Lewis-world_is a cosmos:_according_to_Lewis's final_analysis, an object_none_of whose_parts_bears any "analogically spatiotemporal" relation to_anything_disjoint from it, and which is not_part of any other_such_object. The symbol '↔df'_in (1) and (2) is_supposed to indicate the giving of_an analysis._Perhaps it_may be rendered in English as 'For it to be the_case that... is for it to_be the case that..._'. If_we_have any grip_at_all on_what it means to give an analysis_of something,_we know that pφ ↔df ψq_entails pNecessarily, φ iff_ψq._If this is given up, it_becomes entirely unclear how the meaning_of (1) and (2) go_beyond_the_meaning of the corresponding material_biconditionals.1 So in particular, (1) entails_(1′): 1Is pφ↔df_ψq just equivalent to p(φ↔ ψ)q? There_is_pressure for Lewis to answer yes:_it_wouldn't be so exciting if one_could_analyse_modality, counterfactuals, etc. in nonmodal_terms but still had to take_'↔df' as a primitive, manifestly non-extensional, operator. If one_does answer yes,_one will presumably have a_pragmatic_story_to tell about why claims like 'For Socrates to be_wise is_for Socrates to_be wise and not to be a round square' sound_wrong. 1 (1′) Necessarily: it is possible