8 
PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28 
MALINVAUD 
Yes, I understand that it is your immediate intention; but you 
probably have farther reaching intentions. You want to find new 
sxtensions of the turnpike theorem; but the final purpose of the 
exercise is not clear to me, 
According to the purpose, I would have to look at the paper 
in different ways. If it is purely descriptive, then we should be 
careful that the hypotheses provide, at least as a first approximation, 
a proper description of what happened during the process of growth. 
[f it is oriented towards planning, then we must look at whether 
too many constraints have not be imposed; because, if such were 
‘he case, the results might have little significance for planning. 
Thus, I should appreciate if you could say a little more about 
these broader issues. Perhaps this is not the rule of the game. 
But Professor MAHALANOBIS induced us to look somewhat beyond 
the formal aspects of our theories. 
MORISHIMA 
Well, in various turnpike theorems so far established as well as 
in the original voN NEUMANN model, it is assumed that the supply 
of labour can be expanded indefinitely at the subsistence level of 
real wages; so that it completely ignores the problem of deficiency 
of labour, one of the most serious obstacles to a rapid growth. In 
fact, it is a defect of NEUMANN’s theory of growth that no attention 
's paid to HARROD’s observation that the natural rate of growth sets 
a limit to the maximum average value of the actual rate of growth 
over a long period. 
In this study I am concerned with an economy where the plan- 
ning authorities (or capitalists collectively) make an efficient invest- 
ment planning to produce, at the end of the programming period, 
various outputs in desired proportions. If wages were fixed at the 
subsistence level, capitalists could accumulate stocks of capital goods 
‘9] Morishima - pag. 30