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PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 2» 
the crucial problems of economic development is to make it shift 
so that increases in the real wage are not absorbed by increases in 
the population. This raises a somewhat different ethical problem. 
MORISHIMA 
In this study I have pointed out that the conflict of interest 
between workers and capitalists (or the conflict between present and 
future) will be observed only when the original per-capita consump- 
tion before the technical invention is located in the « perverse » part 
of the curve showing the growth rate of the labour force as a func- 
tion of the per-capita consumption (i.e. that part of the curve in 
which an increase in the per-capita consumption gives rise to a 
decrease in the rate of growth of the labour force). In the « nor- 
mal » part there is no conflict; the extra output due to the increase 
in productivity is shared between the « present » and the « future ». 
MALINVAUD 
Concerning the model itself, I am not very happy about the 
hypothesis that savings come only from capitalists. Not so much 
because I would strongly disagree on the assumption that capitalists 
are saving the larger part of their income, and workers consuming 
the larger part of theirs. But, for already some time in our econo- 
mies, governments have interfered in the distribution of income. 
Hence, I do not find the hypothesis made by Professor MorisHIMA 
very well suited for the practical questions which it is our ultimate 
air to answer. 
MORISHIMA 
My model, although it is oriented toward planning, has no public 
sector. It is implicitly assumed that anv plan for a rapid growth 
9! Morishima - pag. 32