This article argues that the temporality of the financial economy ought to be seen as radically synchronistic. ‘Synchronism’ refers to both an epistemological and practical approach that addresses finance neither with a view to the past nor to the future, but is instead focused on the moment that a financial transaction is settled (i.e., the horizon of trading). From this perspective, the article expands the scope of current social theorizing on financial markets, which is characterized by a preoccupation with the futurity of financial markets and products. It suggests that financial synchronism can be traced back to certain developments in economic theory since the so-called ‘marginalist revolution’, which enabled the transfer of a certain optics informing market theories into financial practices. On these terms, financial synchronism is interpreted as a powerful social imaginary that crucially mediates the way contemporary societies face the contingency of the future.

This paper discusses the concept of contemporaneity as it is used in archaeology. In particular, two general usages are examined. The first concerns the idea of contemporaneity in the context of archaeological dating and chronology, the second relates to the characterization of the archaeological record as a contemporary phenomenon. In both cases, related concepts are explored, namely synchronism and anachronism respectively. The paper offers a critique of these conventional usages of the idea of contemporaneity and argues for an alternative, linking this with the concept of consociation, a term coined by the phenomenologist Alfred Schutz in the early 20th century.

Hydrobia ulvae displays an endogenous rhythm of crawling behaviour of circatidal periodicity, with higher levels of activity during high water. In the present study we address the effect of repeated cycles of immersion and emersion at tidal periodicity on the level and synchronism of the behaviour, by contrasting these with the effects of continuous immersion and continuous emersion. Snails were recorded in dark conditions under the different immersion regimes for 3 days. The results show that continuously emersed snails displayed very low levels of activity. Average activity levels of continuously immersed snails and of those subjected to tidal cycles of immersion and emersion were similar, had identical periods related to the period of the tidal cycle, and had similar phase relationships to the expected tidal cycle. However, form-estimates for these two categories of snails differed, the snails subjected to cyclic conditions showing a larger amplitude and greater synchronism of activity. Therefore, it is concluded that recurrent cycles of immersion and emersion should contribute to well defined cycles of activity in the intertidal environment, with greater activity levels during high water.