Kaldor's Mattioli Lectures analyse a two-sector model with increasing retur
ns to scale (IRS) in industry and diminishing returns in agriculture (DR).
This review article shows that (i) with IRS in industry, a long-run equilib
rium growth path with strictly positive growth rates may exist even if agri
culture is subject to DR; (ii) the industrial sector is the 'engine of grow
th' if agricultural investment is determined passively by available saving;
and (iii) if one introduces a separate agricultural investment function, b
oth positive and negative agricultural supply shocks may lead to stagnation
, thus vindicating Kaldor's emphasis on commodity price stabilisation.