SEMAINE D'ÉTUDE SUR LE ROLE DE L’ ANALYSE ECONOMETRIOUE ETC. 
O1y 
[t goes without saying that, as a straightforward corollary 
of the above results, all aggregate quantities — like gross and 
net national income, consumption, saving, investment, capital 
— increase in real terms, as time goes on, at the same percent- 
age rate of growth (g) of population. 
=. Interesting features of the present case of growth 
The dynamic features of the system considered here, as 
they emerge from the previous sections, are of an extreme sim- 
plicity. The merits of this simplicity are entirely attributable 
to the assumption of a fixed technology and constant returns 
to scale, which confers on this case all the elegant properties it 
possesses. With an invariant technology and constant returns 
to scale, the growth of the system is entirely determined by the 
rate of increase of population. This growth does not affect the 
position of any single individual: per-capita income remains 
constant as time goes on, and economic growth simply means 
that the system expands all its sections in the same proportion. 
All products grow, with population, at the same percentage 
rate, while the structure of the system (its relative composi- 
tion) remains constant as time goes on. 
This case of growth is well known, of course, in economic 
theory. A clear though rudimentary picture of this case can 
already be found in CassEL (°). Recently, LEONTIEF and 
VON NEUMANN, although in a different way (*), have based 
all their well-known dvnamic elaborations exactlv on this case. 
(°) Gustav CasseL, Theoretische Sozialékonomie, Leipzig, 1918, pp. 2 
and ff. English translation: The Theory of Social Economy, London, 1921 
Jp. 34 and fi. 
(®) Both von NEUMANN’s and LEONTIEF’s dynamic models will be discus. 
sed in more detail in an appendix to chapter VI. 
10) Pasinetti - pag. 
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