Prominent among the narratives of explorers whose overt purpose was the expansion of the territory and trade interests of the British Empire, were Samuel Hearne's A Journey from Prince of Wales's Fort in Hudson's Bay to the Northern Ocean (1795) and Alexander Mackenzie's Voyages from Montreal on the River St. Laurence, through the Continent of North America, to the Frozen and Pacific Oceans (1801). Although the two expeditions had similar purposes and their narratives were offered as contributions to empirical knowledge, a comparative study demonstrates that the narratives reflect extremes of empiricism that produce opposite attitudes to natural history and anthropology. I wish to argue that the extremes of empiricism articulated in these narratives therefore call into question Mary Louise Pratt's vision of the imperial enterprise of the time.

In Imperial Eyes, Pratt argues that ‘[f]or three centuries European knowledge-making apparatuses had been construing the planet above all in navigational terms’, but that, in the second half of the eighteenth century, ‘the descriptive apparatus of natural history’ presented a new means for making ‘global-scale meaning’, and thus a new mode for justifying imperial expansion. Justifying imperial expansion was possible because natural history established the European-Self as the guarantor of meaning in relations with non-European Others, by positing the European as the culmination of a natural order of living beings. Pratt's remarks on the systematizing of Nature are in keeping with the concept conveyed by ‘the descriptive apparatus of natural history’. In her analysis of the ways by which travel and exploration narratives employ natural history to legitimate territorial possession, however, Pratt is not speaking of ‘the descriptive apparatus’ as defined according to Michel Foucault's concept of ‘mathesis, understood as a universal science of measurement and order’, but, rather, is speaking of description in the objective or scientific voice, which enables an observer to assume a position of authority when describing objects of observation.

Unlike the observer using the scientific voice to describe according to the system of Nature, the observer using only the scientific voice may speak from a position of authority but does not necessarily assume that authority to be natural.