I WELCOME Professor Sir Geoff Palmer's call for a revision to the teaching of the importance of the slave trade ("Legacy of slavery we must still confront", The Herald, January 9) and the implications for contemporary attitudes.

Analysis of the slave trade can take place at a number of levels. I suggest that, by setting it in context and in a sequence of economic cycles, a revised curriculum approach would have the opportunity to inform students about the nature of economic change and, ultimately, the vulnerability of small nations at the periphery of economic systems. In this scenario, looking out at the world from Scotland is a distortion through a cultural prism, by comparison with looking in from an understanding of the real dynamics of change and power. Professor Tom Devine's appreciation of the "contemporary relevance" of the slave trade as subject matter should surely be to spell out the powerful forces behind economic cycles through history, contextualise Scotland's role, and expose its current economic vulnerability to cultural hysteria.

In response to Prof Devine's comments on "collective amnesia", I feel the greater mistake is the absence of the senses of proportion and sequence. He is right in criticising a mid-19th century start date for historical analysis as too late. I would stress the need for understanding the cycles of economic change and ascendancy, an objective account of the Scottish dimension, and awareness of ongoing cycles of change. The last dimension would spell out Scotland's diminishing mercantile and manufacturing role and underwrite understanding of the contemporary fragility of a peripheral economy.

The importance of understanding the slave trade is because of its global importance, not Scotland's share of profit or guilt or individuals' roles in securing abolition. The slave trade existed because of slavery, in turn mandated by the rise of an Atlantic economy based on the plantation system. The appropriate context is, therefore, the nature of economic systems rather than the actions of individuals. Equally, it is a dynamic scenario, with different economic systems in the ascendant and the period of the Atlantic slave trade simply one phase in the development of what Immanuel Wallerstein has described as the Modern World System. And it would be apposite to point out to students that the Atlantic slave trade was preceded by a vigorous economic phase in Africa, with competing continental empires and a trans-Saharan slave trade.

Africa before the period of the Atlantic slave trade had a developed economic, technological and political system perhaps in advance of late medieval/early modern Europe. Africa's under-development begins with the power dynamics of the Atlantic slave trade, is consolidated by the commodity trade of the 19th century, and sustained through colonial conquest and domination. The appropriate outcome to a study of the slave trade is to demonstrate the ascendancy of economic systems based on control of resources, raw materials and the means of production. These advantages translate into military power and sustained domination. The control of the slave trade by Western nations gave them domination over Africa that has continued to the present and interrupted a previous parallel pattern of development between Europe and Africa.

The phases move on: plantation systems give way to manufacturing and the locus of manufacturing shifts power further to Europe and North America. Subsequent phases through the 20th century see comparative advantage in manufacturing shift to the Far East. The contemporary domination of manufacturing and technology-based economies in the Far East and China is translating into the rise of the demographically advantaged Bric countries (Brazil, Russia, India and China) and providing opportunity to the Mint countries (Mexico, Indonesia, Nigeria and Turkey). The latter grouping shows the first emergence of nations previously on the periphery or semi-periphery, but now taking advantage of population scale and distribution (particularly the younger age profile as a percentage of total population) as well as strong emphasis on core elements of a knowledge economy.

The phases in which Scotland was able to demonstrate a dispropor-tionate role in mercantilist systems and manufacturing have long passed. Understanding that our ability to influence economic change on the wider scale has ended could translate creatively into revised curriculum approaches focused on identifying forces for change in history and a sense of balance and objectivity around Scotland's current assets and best options.

Professor Bill Wardle,

Southbrae Drive, Glasgow.