According to the editors of an influential text in the history of social science, “in the first half of the nineteenth century the expression series seemed destined to a great philosophical future”. The expression itself seems to encourage speculation on destiny. Elements laid out in a temporal sequence ask to be continued through the addition of subsequent terms. “Series” were particularly prominent in the French Restoration and July Monarchy (1815–48) in works announcing a new social science. For example, the physician and republican conspirator J. P. B. Buchez, a former follower of Henri de Saint-Simon who led a movement of Catholic social reform, made “series” central to his Introduction a la science de l’histoire. Mathematical series show a “progression”, not “a simple succession of unrelated numbers”; in human history, we discover two simultaneous series: “one growing, that of good; one diminishing, that of evil.” The inevitability of positive progress was confirmed by recent findings in physiology, zoology and geology. Correlations between the developmental stages of organisms, species, and the Earth were proof that humanity’s presence in the world “was no accident”, and that “labour, devotion and sacrifice” were part of the “universal order”. The “great law of progress” pointed toward a socialist republic in fulfilment both of scripture and of the promise of 1789. For Buchez, as for many of his contemporaries, series both described and predicted. At the same time, they were a call to action. This period gave birth to two closely related neologisms: “sociology”, coined by Auguste Comte, and “socialism”, which entered French in the works of Pierre Leroux. Both terms were shaped by new experiences of time. Michel Foucault offered one perspective on these changes in his archaeology of the human sciences: the modern episteme, he wrote, was defined by the replacement of static series by historical series. At the end of the eighteenth century, the temporal pre-eminence of classificatory tables of differences and identities, including the “animal series” stretching from the simplest organisms up to man, gave way to the temporally oriented series of language, life and labour: philology’s sequences of roots and inflections, Cuvier’s “micro-series” of organs and “macro-series” of organisms, and the “great linear, homogeneous series ... of production” identified by Ricardo. According to Foucault these newly historically-minded disciplines provided models for the “hazy” knowledge in the human and social sciences and shaped the temporal orientation