ON THE FOURTH DAY of December 1893, Joseph Friedrich Nicolaus Bornmüller bent down and picked leaves from a low shrub with small white flowers. Bornmüller was on a botanical collecting trip through the Middle East, and he had just discovered a new species of pennycress. The dried specimen of Thlaspi syriacum he preserved on a sheet of paper is now housed in the herbarium of the Berlin-Dahlem Botanical Museum of the Freie Universität Berlin. These crumbling leaves are the holotype of the Thlaspi syriacum species. The word holotype is derived from the Greek ὅƛος—“whole, entire.” Bornmüller's sample was the basis for the description of the whole species. Every subsequent identification of an individual plant as Thlaspi syriacum or not Thlaspi syriacum is, in theory, based on whether or not that individual conforms to the appearance of the leaves Bornmüller plucked somewhere in what is now Syria. Holotypes are artificial. Bornmüller's hand was not guided to the most perfect specimen of Thlaspi syriacum. Rather, he anointed one individual plant to be the representation of a schema of botanical collecting and categorizing. This artificial creation and use of a holotype works for botanists, since they (usually) care more about the ways in which individual plants of the same species are similar rather than the ways in which they are different. They ignore the differences between individual embodiments (this patch of Thlaspi syriacum by the side of the road) and the abstract generalization (the Berlin holotype).

Cultural artifacts do not admit of so easy a negation of the value of the individual. We would rightly hesitate to discard even very similar cultural artifacts. Even reprintings of the same text can each have different value. The text of Alexander Pope's poem “The Rape of the Lock” is the same in the volume of John Bell's Travelling Poetic Library, bound in elaborately gilt calfskin and purchased in Paris in October 1785 by Thomas Jefferson for his twelve-year old daughter Martha, and in the battered paperback that I bought for a dollar from the bins of a used bookstore. But each of these volumes has a different history and a different set of relationships with the people who produced and used them. Some of these histories are more interesting than others.