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␈↓ α∧␈↓α␈↓ ¬↓COMMENTS ON DENICOFF PAPER

␈↓ α∧␈↓␈↓ αTMarvin␈α
Denicoff␈α
does␈α
a␈α
real␈α
service␈α
in␈α
attempting␈α
a␈α
history␈α
of␈α
computing,␈α
and␈α
his␈αtopics␈α
are
␈↓ α∧␈↓well␈αchosen.␈α However,␈αit␈αis␈αone␈αof␈αthe␈αfirst␈αattempts␈αand␈αnaturally␈αencounters␈αdisagreement␈αfrom
␈↓ α∧␈↓other participants and observers.  Here are mine:

␈↓ α∧␈↓␈↓ αT1.␈α
On␈α∞the␈α
whole␈α
the␈α∞fifties␈α
were␈α∞more␈α
optimistic␈α
years␈α∞than␈α
the␈α
seventies␈α∞and␈α
not␈α∞only␈α
in
␈↓ α∧␈↓computer␈α∩science.␈α∩ However,␈α∩the␈α∩picture␈α∩drawn␈α∩by␈α∩Denicoff␈α∩doesn't␈α∩do␈α∩justice␈α∩to␈α∩the␈α∩varied
␈↓ α∧␈↓opinions␈α
extant␈α
at␈α
that␈α
time␈α
about␈α
the␈αprobabilities␈α
of␈α
success␈α
of␈α
various␈α
endeavors␈α
in␈αgiven␈α
times.
␈↓ α∧␈↓When␈α∂asked␈α⊂for␈α∂a␈α⊂prediction␈α∂of␈α⊂how␈α∂soon␈α∂a␈α⊂research␈α∂or␈α⊂development␈α∂goal␈α⊂will␈α∂be␈α⊂realized,␈α∂a
␈↓ α∧␈↓scientist␈α∞is␈α∞bound␈α∞to␈α
give␈α∞an␈α∞optimistic␈α∞answer␈α
if␈α∞he␈α∞takes␈α∞into␈α
account␈α∞only␈α∞difficulties␈α∞that␈α
he
␈↓ α∧␈↓recognizes.␈α
 Therefore,␈αhe␈α
should␈αcautiously␈α
answer␈αthat␈α
if␈αthe␈α
difficulties␈αhe␈α
sees␈αare␈α
all␈αthere␈α
are,
␈↓ α∧␈↓it will take ␈↓↓n␈↓ years.

␈↓ α∧␈↓␈↓ αT2.␈αDenicoff's␈αhistory␈αof␈αtime-sharing␈αassigns␈αto␈αlittle␈αcredit␈αto␈αCorbato␈α(who␈αinitiated␈αCTSS)
␈↓ α∧␈↓and␈α∂me␈α∞and␈α∂too␈α∂much␈α∞to␈α∂Strachey␈α∞(read␈α∂his␈α∂1959␈α∞paper),␈α∂Teager,␈α∞and␈α∂Fano.␈α∂ Institutionally,␈α∞it
␈↓ α∧␈↓neglects␈α
the␈α
IBM␈α
and␈α
NSF␈α
support␈α
of␈α
early␈α
time-sharing␈α
at␈α
M.I.T.␈α
and␈α
N.I.H.␈α
support␈α
of␈α
time-
␈↓ α∧␈↓sharing␈α∃at␈α∀BBN.␈α∃ Administratively,␈α∀Philip␈α∃Morse␈α∀and␈α∃J.C.R.␈α∀Licklider␈α∃also␈α∃deserve␈α∀credit.
␈↓ α∧␈↓Fredkin␈αdeserves␈αcredit␈αfor␈αrecognizing␈αthat␈αtime-sharing␈αwas␈αfeasible␈αon␈αa␈αcomputer␈αas␈α
small␈αas
␈↓ α∧␈↓the␈α
PDP-1␈α
and␈α
devising␈α
most␈α
of␈α
the␈α
hardware␈α
modifications␈α
required␈α
to␈α
make␈α
it␈α∞feasible.␈α
 The
␈↓ α∧␈↓importance␈α∪of␈α∪MULTICS␈α∪is␈α∪exaggerated;␈α∪it␈α∪never␈α∪produced␈α∪cost-effective␈α∀time-sharing␈α∪and
␈↓ α∧␈↓neither␈α
did␈α∞the␈α
IBM␈α∞TSS␈α
effort.␈α∞ Denicoff␈α
inexplicably␈α∞totally␈α
ignores␈α∞the␈α
PDP-6␈α∞and␈α
PDP-10
␈↓ α∧␈↓computers␈α∂which␈α∂initiated␈α∂cost-effective␈α∂time-sharing␈α⊂and␈α∂whose␈α∂descendants␈α∂are␈α∂still␈α⊂the␈α∂most
␈↓ α∧␈↓commonly␈αused␈α
time-sharing␈αmachines.␈α Their␈α
success␈αcompared␈α
to␈αMULTICS␈αand␈α
TSS␈αis␈αdue␈α
to
␈↓ α∧␈↓concentrating␈α⊂on␈α⊂real␈α⊂problems␈α⊂rather␈α⊂than␈α⊂the␈α⊂pseudo-problems␈α⊂such␈α⊂as␈α⊂levels␈α⊂of␈α⊃access␈α⊂and
␈↓ α∧␈↓extreme elaboration of paging and segmentation.

␈↓ α∧␈↓␈↓ αT3.␈αArtificial␈αintelligence.␈α The␈αDartmouth␈αconference␈αwas␈αin␈α1956.␈α The␈αhistory␈α
of␈αartificial
␈↓ α∧␈↓intelligence␈α∞is␈α∞even␈α∂harder␈α∞to␈α∞write␈α∂than␈α∞that␈α∞of␈α∂time-sharing.␈α∞ Time-sharing␈α∞is␈α∂successful,␈α∞and
␈↓ α∧␈↓careful␈α∀interviewing␈α∀and␈α∀reading␈α∀will␈α∀trace␈α∀the␈α∀successful␈α∀ideas␈α∀to␈α∀their␈α∀sources.␈α∪ Artificial
␈↓ α∧␈↓intelligence␈α
has␈α∞not␈α
yet␈α∞achieved␈α
enough␈α∞of␈α
its␈α
goals␈α∞to␈α
make␈α∞it␈α
uncontroversial␈α∞which␈α
activities
␈↓ α∧␈↓are␈αcontributions␈αand␈αwhich␈αare␈αblind␈αalleys.␈α Moreover,␈αthe␈αtheoretical␈αfoundation␈αof␈αthe␈αsubject
␈↓ α∧␈↓is␈α∂still␈α∂so␈α∂undeveloped␈α∂that␈α∂it␈α∂can't␈α∂even␈α∂be␈α∂definitively␈α∂said␈α∂what␈α∂the␈α∂basic␈α∂ideas␈α∂are.␈α∂ E.g.␈α∞is
␈↓ α∧␈↓natural language understanding fundamental or a side issue?

␈↓ α∧␈↓␈↓ αT4.␈α
Software␈αdevelopment.␈α
 I␈αfind␈α
this␈α
discussion␈αmixing␈α
issues␈αof␈α
management,␈αlanguage␈α
and
␈↓ α∧␈↓data structure design, and proofs of correctness rather murky.

␈↓ α∧␈↓␈↓ αT5.␈α
Large␈α
file␈α
systems.␈α
 One␈α
suspects␈α
the␈α
author␈α
of␈α
overemphasizing␈α
activities␈α
sponsored␈αby
␈↓ α∧␈↓ONR.␈α The␈αpacing␈αelement␈αin␈αlarge␈αon-line␈αdata␈αsystems␈αhas␈αbeen␈αthe␈αcost␈αof␈αdisk␈αfile.␈α Now␈αthat
␈↓ α∧␈↓disk␈αfiles␈αare␈αcheap,␈αthere␈αcan␈αbe␈αmovement␈αaway␈αfrom␈αmonthly␈αbatch␈αprocessing␈αof␈αkeypunched
␈↓ α∧␈↓data␈αto␈αimmediate␈αprocessing␈αof␈α
data␈αentered␈αat␈αterminals␈αas␈α
soon␈αas␈αit␈αis␈αreceived␈αwith␈α
immediate
␈↓ α∧␈↓feedback␈αto␈αthe␈αperson␈αwho␈αenters␈αthe␈αdata.␈α This␈αchange␈αis␈αimportant␈αfor␈αsocial␈αreasons,␈αbecause
␈↓ α∧␈↓much␈α∂of␈α∂the␈α∂rigidity␈α⊂and␈α∂mystery␈α∂of␈α∂computer␈α∂systems␈α⊂has␈α∂been␈α∂caused␈α∂by␈α∂the␈α⊂infeasibility␈α∂of
␈↓ α∧␈↓interrogating␈α
and␈α
changing␈αdata␈α
relevant␈α
to␈αan␈α
individual␈α
in␈αthe␈α
middle␈α
of␈αa␈α
large␈α
tape␈αlibrary.
␈↓ α∧␈↓The problem may be important enough to almost justify outlawing batch processing.



␈↓ α∧␈↓␈↓ ε|1␈↓ ∧