The life of Robert Malthus (1766-1834) spanned the decades in Britain of the rapid transition towards mass international migration. In 1826/7, in his famous explication before the Emigration Committee of Parliament, Malthus argued that the ineffectiveness of emigration as a permanent remedy was a consequence of the 'vacuum effect'. He proposed a series of apparently inescapable tendencies regarding the causes and consequences of population growth, which were generally 'dismal'. Malthus' best-known propositions about emigration related to the utility or otherwise of emigration as a means of relieving the pressure of population on subsistence. There exists a debateable let-out clause for Malthus, located in his doctrine concerning the longer-run. There was less rigidity and less pessimism in Malthusian doctrine than is conventionally understood. The most favoured explanation of the demographic order relates to the escape from 'the Malthusian trap'.