PsyPhilProg

TedNewardNeward&Associates

http://www.tedneward.com|ted@tedneward.com

WhoamI?

TedNeward,"ComputationalPhilosopher"– thismeansIliketowrestlewithreallyinteresting/hardquestionsthatoftenhavenoanswers,andevenmoreoftencreatemorequestions•theactualitiesofartificialintelligence•interviewprocesses•howtomanagedevelopers

– IlookforanswersintheLiberalArtshistory,psychology,economicsandparticularlyphilosophy

Architecture

Whatdefinesthedifferencebetweenthesetwobuildings?– goals– scope– complexity– materials– process– …?

Objectives

Programmingisanextremelyephemeralactivity– wecannotseeit--onlyitsside-effects– wecannottouchit--onlythemachinewithinwhichitiscontainedandsometimesnoteventhen

– wecannotobserveitdirectlyinfact,werequiremoresoftwaretodiagnoseandcorrectit

Objectives

Givenhowmuchwerelyonourunderstandofabstractions...

...weprobablyshould...Psychology

•...understandwherethoseabstractionslive•...understandhowthoseabstractionscometoexist•...understandthelimitationsofthoseabstractions

Philosophy•...learnwhattoquestionandwhy•...cometogripswithwhatweknowanddon'tknow•...beginwhereallsciencebegan

Philosophy

What,exactly,isit?

Philosophy

Whatisphilosophy?– "loveofwisdom"(AncientGreek)– thefundamentalrootofallthinking– thebasisofallscience– "scienceinonehand,andreligionintheother"– thecentralquestionthatphilosophyseekstoanswer

Philosophy

Ironically,mostofusare(already)philosophers– whatshouldwedo?– whatisthere?– howdoweknow?ifwedon'tknow,howshouldwesetaboutfindingout?

Philosophy

Majorbranchesofphilosophy– Metaphysics

examiningwhatexists,thedifferencebetweenmindandmatter,andsoon

– Epistemologyhowdoweknowathing?howdoweacquireknowledge?whatisthenatureofknowledge?

– LogicAristoteliansyllogismsupthroughmathematicalandsymboliclogic

Philosophy

Majorbranchesofphilosophy– Moralphilosophyandethics

whatisright?whatisevil?whatisvirtue?whatdoesitmeantoliveagoodlife?

– Politicalphilosophywhatarethe"unassailablehumanrights"?whatistherelationshipbetweengovernmentandthegoverned?

– Aestheticswhatisbeauty?whatisart?

Philosophy

RogerScruton("AShortHistoryofPhilosophy")– twodistinguishingcharacteristicsofphilosophicalthought

•abstraction•concernfortruth

– "Problemsofphilosophyandthesystemsofdesigntosolvethemarepopulatedintermswhichtendtorefernottotherealmofactuality,buttotherealmsofpossibilityandnecessity:towhatmightbeandwhatmustbe,ratherthanwhatis"

Philosophy

Philosophyischaracterizedbyseveralthings– studentsareencouragednottoaccepttheconclusionsoftheirteachers,buttodiscuss,argueanddisbelieve

– argumentsarerootedinlogicandreason,notfaithorbelief

Philosophy

Mostsciencebeginsasphilosophy– "Ithasoftenbeenremarkedthatwhenanareaofinquirybeginstofinditsfeetasadiscipline,withclearlyagreedmethodsandaclearlyagreedbodyofknowledge,fairlysoonitseparatesofffromwhathasuptothenbeenknownasphilosophyandgoesitsownway."

– suchas....•physics•chemistry•astronomy•psychology

– somecontinuetomaintaintightrelationships

TheSoritesParadox

Exerciseinphilosophicalthought

TheSoritesParadox

Whendoindividualgrainsofsandbecomeaheap?

TheSoritesParadox

Whendoindividualgrainsofsandbecomeaheap?

Moreimportantly,whydoesthisparadoxtakeplace?

Zeno'sParadoxes

Findtheflawintheargument

Zeno'sParadoxes

ThegodApolloandaturtlearegoingtorace

Zeno'sParadoxes

ThegodApolloandaturtlearegoingtoraceApollogivestheturtleahugeheadstart

Zeno'sParadoxes

ThegodApolloandaturtlearegoingtoraceApollogivestheturtleahugeheadstartButifApollomakesuphalfthedistancebetweenhim

andtheturtleeverysecond...

Zeno'sParadoxes

ThegodApolloandaturtleaegoingtoraceApollogivestheturtleahugeheadstartButifApollomakesuphalfthedistancebetweenhim

andtheturtleeverysecond......hecannevercatchtheturtle!

Zeno'sParadoxes

Anarrowisloosedfromabowtoflythroughtheair

Zeno'sParadoxes

AnarrowisloosedfromabowtoflythroughtheairButinanysinglemomentintime,thearrowisnot

moving

Zeno'sParadoxes

AnarrowisloosedfromabowtoflythroughtheairButinanysinglemomentintime,thearrowisnot

moving...thereforethearrowisnotreallymovingatall!

Xenophanes

Earlythoughtsonwhatweknow

Xenophanes

XenophanesofColophon(570- 475?BC)– exiledtoSouthernItaly– criticizedHomerianconceptofanthropomorphizedgods– thefirsttoactuallyengageinevidence-basedargument– histhoughtscenteredaroundthenatureofknowledgeitself

Xenophanes

Godsareareflectionoftheculturethatworshipsthem– 'theEthiopiansmaketheirgodsblackandsnub-nosed;– 'theThracianssaytheirshaveblueeyesandredhair.– 'ifoxenandhorseshadhandsandcouldpaint,– 'oxenwouldpainttheirgodsasoxen,andhorsesashorses.'

Xenophanes

Naturalnatureoftheuniverse:Mud– hehadnoticedfossilremainsintheearth– guessedthatperhapstheworlddriedup

•thusreturningtoitsoriginalmuddystate•trappingandpreservingthecreaturesasitdid

Xenophanes

Truebelief– whenwesaywe"know"something,thatknowledgeisactuallyonlya"truebelief"ahypothesisgoodenoughforustoworkfrom

– hemaintainedthata"truthofreality"didexist,butwillalwaysbebeyondourhumanunderstandingthebestwecandoisrefineourhypothesescontinuallytogetnearertoit

– leadstoamethodologyoffalsificationpickedupinmoderntimesbyKarlPopper

Psychology

Thestudyofbehavior

Psychology

Psychologyis...– "thescientificstudyofthehumanmindanditsfunctions,especiallythoseaffectingbehaviorinagivencontext"

– "thementalcharacteristicsorattitudeofapersonorgroup"

Psychology

Fivemainperspectives– Biological

therelationshipofthebodyandthemind– Learning

long-lastingchangeinthewayaperson/animalbehavesthatisattributableexperience

– Cognitivestudyofmemory,perception,thoughtandothermentalprocesses

– Socioculturalhowsocialenvironmentandculturalbeliefsshapeourlives

– Psychodynamicstudyofunconsciousmotivesanddesires

'Psychomythology'

"Commonsenseisnotsocommon"--Voltaire(1764)

Psychomythology

"Oppositesattract""Sparetherod,spoilthechild""Familiaritybreedscontempt""There'ssafetyinnumbers"

Psychomythology

Thesearepopularsayings/platitudes– mostpeopleholdthemtobeself-evident– when,infact,sciencerepudiatesalloftheabove– manyofthese"facts"comefromthe"poppsychology"world

Psychomythology

Somepopularpsychological"facts"– "Weonlyuse10%ofourbraincapacity"– "Ifweareangry,it'sbettertoexpresstheangerdirectlythanholditin"

– "Mostsexually-abusedchildrengrowuptobecomeabusersthemselves"

– "Peoplewithschizophreniahave'split'personalities"– "Peopletendtoactstrangelyduringafullmoon"

Alloftheseareverifiablyfalse

ReasonsforPsychomythology

Whydowebelieveinfalsehoods?

Reasons

Insomecases,wearemisledbysupposedexperts– "DrPhil"likestousetheliedetectoronhisshow

wheninfactliedetectorsarenotnearlyasaccurateasassumed

– popularauthorswillsometimesgetthepsychologywrongweareforcedtoaccepttheirclaimsonfaithalone

– ortheywillexplainonlypartsofitbecausetheywanttokeepourattention

– ortheirreaderswillonlyholdontothesimplestpartsofitbecauseourmemoryisfallibleandweseekpatterns

Reasons

Insomecases,webelievewearetheexperts– orcloseenough,anyway--howhardcanitreallybe?– "ifIamsmartenoughtodo(somecomplicatedactivity),Iamsmartenoughtounderstandthisotherstuff"it'swhatleadsdoctorstobelievetheyarelawyers,andlawyerstobelievetheyarerocketscientists,andsoon

– thisishubrisitisadifficultthingtoovercome;itrequiresaconstantself- orexternally-imposedmonitoringofourthoughtsandactions

Reasons

Insomecases,thescienceis"closeenough"– ...butnotperfect– example:'ulcersarecausedbybody'sreactiontostress'

•nocure;"lower-stresslifestyleandamanageddiet"•twoAustralianresearchers(BarryMarshall,RobinWarren)discoveredbacteriuminthestomach•"notpossible--nothingcouldsurvivehumanstomachacid"•meet"Helicobacterpylori":itdoes,infactsurviveinthestomach•...andtheseulcerscanbetreatedbyeverydayantibiotics•...andtheywonaNobelPrizeforit•theyweren'tthefirstto"discover"it;ithadbeenspottedbyatleastthreeseparateteamsofresearchersacenturyearlier

Reasons

Insomecases,itcontradictsourcommonsense– ourbrainsaregoodatinterpretingtheworld– ourbrainsareterribleatinterpretingourbrains

JacobBronowski(1966)calledthis"reflexivity"– thereisnotyetanykindof"debugger"forthebrain

thoughwemaybegettingcloser....

Reasons

PsychologicalSciencevs"Commonsense"– TalkshowhostDennisPrager:

"Therearetwokindsofstudiesintheworld:thosethatconfirmourcommonsense,andthosethatarewrong""Useyourcommonsense.Wheneveryouhearthewords'studiesshow'--outsideofthenaturalsciences--andyoufindthatthesestudiesshowtheoppositeofwhatcommonsensesuggests,beveryskeptical.Idonotrecallevercomingacrossavalidstudythatcontravenedcommonsense.(Prager,2002,p1)"

– MalcolmGladwellgetsintothis("Blink")

Reasons

Andyet...scienceis"uncommonsense"– "Phrenologycandetermineyourpersonality"– "X-Raysareharmlessfestivalentertainment"– "Emotionsoriginatefromtheheart"– "Womenarelessintelligentthanmen"– "Thebodyismadeupoffour'humours':blood,blackbile,yellowbileandphlegm"thoselastthreewereAristotle'sbeliefs

Reasons

Andyet...scienceis"uncommonsense""Nothingcouldbemoreobviousthanthattheearthisstableandunmoving,andthatwearethecenteroftheuniverse.ModernWesternsciencetakesitsbeginningfromadenialofthiscommonsenseaxiom...Commonsense,thefoundationofeverydaylife,couldnolongerserveforthegovernanceofworld.(Borstin,1983,p.294)"

Reasons

Thisdoesn'tmeanallcommonsenseiswrong– happyemployeesgetmoreworkdonethanunhappyones

Butitdoesmeanthatweneedtotreatcommonsensewithskepticism– if"everybodyknows",thenmaybethey'rewrong

Psychomythology:Sowhat?

Whatcanithurt?

Sowhat?

Whatrealdamageistheretobelievinginafewfolktales?– nobodyeverdiedfrombelievinginGreekmyths,right?

Sowhat?

Psychologicalmythscanbeharmful– jurorswhobelievememoriesarelikevideotapewillvotetoconvictadefendantonthebasisofconfidently-heldinaccurateeyewitnesstestimony

– parentswhobelievepunishingchildrenisaneffectivemeansofchanginglong-termbehaviorwillachievetheopposite

– doctorswhorefusetoallowtheirauthoritytobequestionedwillcontinuetokillpatients

Sowhat?

Psychologicalmythscancauseindirectdamage– thebeliefthatweare"rationalactors"whenwemakeeconomicdecisions

– peoplewastemoneyon"subliminalself-helptapes"– wemaymakedecisionsbasedoninaccurateinformation(suchasapoliticalcandidate'shonestyorwhatthey'vesaidornotsaid

Sowhat?

Theacceptanceofpsychologicalmythscanimpedeourcriticalthinkinginotherareas– ourfailuretodistinguishmythfromrealityinonedomainofscientificknowledgecaneasilyspillovertoafailuretodistinguishfactfromfictioninotherareas(CarlSagan)

– asaconsequence,wemayfindourselvesatthemercyofpolicy-makerswhomakeunwiseand/ordangerousdecisions

– "Knowledgeispower;ignoranceispowerlessness"SirFrancisBacon

Bustingpsychomythology

Clearingoutthegarbage

Psychomythbusting

Amythbustingtoolkit– thesearetencommonsourcesoferror– compensateforthemwheneverusedorseen

Psychomythbusting

Tensourcesoferror– Word-of-Mouth("urbanmyths")– DesireforEasyAnswersandQuickFixes– SelectivePerceptionandMemory– InferringCausationfromCorrelation– PostHoc,ErgoPropterHocReasoning

"afterthis,thereforebecauseofthis"

Psychomythbusting

Tensourcesoferror– ExposuretoaBiasedSample– ReasoningbyRepresentativeness

bewareofheuristics(mentalshortcuts/rulesofthumb)– MisleadingFilmandMediaPortrayals– ExaggerationofaKernelofTruth– TerminologicalConfusion

Perception

Notquiteasobjectiveasyouthink

Perception

Literalvisualandauditorystimuliisnottheendofthestory– rodsandconesinterpretcolorsofwhatwesee– butimagesareeasily"separated"intogroups– thebraininterpretsimagesusingaformofpatternrecognition

Perception

GestaltPsychology– aschoolofthoughtoriginatinginGermanyintheearly1900s

– peopleorganizevisualinformationintopatternsandforms– thisexplainsmanyopticalillusions,forexample

Perception

GestaltPrinciples– Figureandground

•"figure"iswhatstandsout•"ground"isthebackdropinwhichthefigureappears

– Proximitywhenobjectslieclosetogether,objectsareperceivedasagroup

– Closureinterpretfamiliar,incompleteformsascompletebyfillingingaps

Perception

GestaltPrinciples– Similarity

•groupsimilarobjectstogether•theninterpretthelargerpattern

– Continuityinterruptedlines/patternsareinterpretedtobecontinuousw/gaps

– Simplicityperceivesformsassimple,symmetricalfiguresratherthanirregularones

Perception

DepthPerception– inordertoperceivedistance,weusebinocularandmonocularcues

– binocular:cuesthatrequirebotheyes– monocular:cuesthatrequireonlyoneeye

Perception

Binocularcues– Retinaldisparity

•theeyeslieafewinchesapart•thustheirretinasthuspickupslightlydifferentimagesofobjects•retinaldisparityincreasesastheeyesgetclosertoanobject

– Convergence•theeyesmustturn"inward"(towardseachother)tolookatanobjectclose-up•theclosertheobject,themoremusclemovement•thus,themoremusclemovement,theclosertheobjectis

Perception

Monocularcues– Interposition

whenoneobjectisblockingpartofanother,theblockedobjectappearsfurtheraway

– Motionparallax(relativemotion)•whentheviewerismoving,stationaryobjectsappeartomoveindifferentdirections/speedsdependingontheirlocation•themoredistanttheobject,thesloweritmoves•theclosertheobject,thefasteritmoves

– Relativesizepeopleseeobjectsthatmakeasmallerimageontheretinaasfartheraway

Perception

Monocularcues– Relativeclarity

objectsthatappearcharp,clearanddetailedareseenascloserthanhazyobjects

– Texturegradientsmallerobjectsthataremorethicklyclusteredappearfartherawaythanobjectsthatarespreadoutinspace

– Linearperspective•parallellinesthatconvergeappearfartheraway•themorethelinesconverge,thegreatertheperceiveddistance

– Lightandshadowpatternsoflight/shadowmakeobjectsappearthree-D

Perception

Perceptualconsistency– theabilitytorecognizethananobjectremainsthesameevenwhenitproducesdifferentimagesontheretina

– shapeconstancy– sizeconstancy– brightnessconstancy– colorconstancy– locationconstancy

Perception

Perceptualset– thereadinesstoseeobjectsinaparticularwaybasedonexpectations,experiences,emotions,andassumptions

Perception

Selectiveattention– theabilitytofocusonsomebitsofsensoryinformationandignoreothersthisiswhatallowsyoutoreadtheseslidesorwatchthistalk!

Perception

Contexteffects– peoplesimmediatesurroundingscreateexpectationsthatmakethemseeinparticularways

Summary

Finishingup

Summary

Whatdowedowiththis?– whatmakesgoodcode?whatisagoodprogrammer?– howdowehirethebest?howdowekeepthem?– doesagileactuallywork?orwas/istheresomethingelseactuallyatwork?

– managingcustomerinteractions/interviews