whom he had served in the army (and to whom the work is dedicated). As for the nocturnal hours spent writing, these were seen not as a loss of sleep but as an addition to life, for as he states in the preface, Vita vigilia est, "to be alive is to be watchful", in a military metaphor of a sentry keeping watch in the night. Pliny claims to be the only Roman ever to have undertaken such a work, in his prayer for the blessing of the universal mother:

The Natural History is encyclopedic in scope, but its format is unlike a modern encyclopedia.