Ego-documents are at the heart of historical sociolinguistics. Contrary to what a label such as ego-document may suggest, Early and Late Modern ego-documents constitute a heterogenous group of... Show moreEgo-documents are at the heart of historical sociolinguistics. Contrary to what a label such as ego-document may suggest, Early and Late Modern ego-documents constitute a heterogenous group of genres comprising, among others, private letters, diaries and travel journals. Empirical studies have shown that there are important linguistic differences between private letters on the one hand, and diaries/journals on the other. The latter often seem surprisingly standard-like or formal. Theoretical models of register variation and conceptual orality can partially explain the differences, without however offering a full explanation of the surprising formality of diaries/journals. We argue that it is crucial to take into account recent work by social historians concerning diaries/journals in the eighteenth and nineteenth centuries. Diary-writing was an inherently reflexive practice allowing authors to reflect on their lives, and to create a textually fixed point of reference. Authors of diaries had a variable and multilayered audience in mind of known and unknown readers. We introduce the observee’s paradox: while creating private texts for themselves in which they were their own observers and observees, authors of diaries also reckoned with unknown readers in a possibly distant future, which prompted them to shift into a more formal or standard-like register. Show less