ency' of population to outrun the
means of subsistence. Yet he holds unequivocally that the increase of
population has been accompanied by an increased comfort; that want has
diminished although population has increased; and that the
'preventive' check is stronger than of old in proportion to the
positive check. Scotland, he says,[225] is 'still overpeopled, but not
so much as when it contained fewer inhabitants.' Many nations, as he
points out in general terms, have been most prosperous when most
populous.[226] They could export food when crowded, and have ceased to
import it when thinned. This, indeed, expresses his permanent views,
though the facts were often alleged by his critics as a disproof of
them. Was not the disproof real? Does not a real evasion lurk under
the phrase 'tendency'? You may say that the earth has a tendency to
fall into the sun, and another 'tendency' to move away from the sun.
But it would be absurd to argue that we were therefore in danger of
being burnt or of being frozen. To explain the law of a vital process,
we may have to analyse it, and therefore to regard it as due to
conflicting forces; but the forces do not really exist separately, and
in considering the whole concrete phenomenon we must take them as
mutually implied. A man has a 'tendency' to grow too fat; and another
'tendency' to grow too thin. That surely means that on the whole he
has a 'tendency' to preserve the desirable mean. The phrase, then, can
only have a distinct meaning when the conflicting forces represent two
independent or really separable forces. To use an illustration given
by Malthus, we might say that a man had a 'tendency' to grow upwards;
but was restrained by a weight on his head. The man has the
'tendency,' because we may regard the weight as a separable accident.
When both forces are of the essence, the separate 'tendencies'
correspond merely to our way of analysing the fact. But if one can be
properly regarded as relatively accidental, the 'tendency' means the
way in which the other will manifest itself in actual cases.

In 1829, Senior put this point to Malthus.[227] What, he asked, do you
understand by a 'tendency' when you admit that the tendency is
normally overbalanced by others? Malthus explains his meaning to be
that every nation suffers from evils 'specifically arising from the
pressure of population against food.' The wages of the labourer in old
countries have never been sufficient to enable him to