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PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 2& 
WoLD 
I have two comments. The first refers to the entire group of 
four papers presented to-day (1), all of which deal with purely 
theoretical highly simplified models of economic growth. This kind 
of logical analysis has a strong appeal, and that it has a wide 
appeal is clear from the fact that the three other papers are closely 
interrelated both with regard to problems and results. 
My second comment refers specifically to Professor MORISHIMA’s 
paper, and is a question about the proportionality assumption on 
page 7 (3). Am I right to understand that this assumption requires, 
for example, that the demand for food remains a constant fraction 
of GNP as the economy grows? If yes, the assumption is in radical 
contrast to the whole outlook of a later paper to-day, that of Pro- 
fessor GALE JonnsoN. There the whole emphasis is shifted. There 
exists no such proportionality; on the contrary, the lack of propor- 
tionality is a universal handicap for the farming population. 
ALLAIS 
I have two remarks to make. The first was made by Prof. 
Worp, namely that there are some quite strong hypotheses in the 
model. 
Secondly, I have unfortunately not had the time to study Pro- 
fessor MORISHIMA’s paper very carefully since I was working in the 
other group. But so far as I can judge, the MorisHIMA’s model 
is a special case of a general theory I presented this year in my 
paper for the Cambridge Round Table of the International Economic 
Association. Thank vou. 
(!) Koopmans, MALINVAUD, MORISHIMA, PASINETTI. 
(3) The discussions having been organized in two separate groups during 
a first phase of the Study Week, my question belongs to the second phase 
of joint discussion. Now when reading the proofs I see that a similar 
question was posed in the separate discussion, but T repeat the question 
to mark the importance of the issue 
9] 
Morishima - pag. 40