|Yesterday is between Sunday, 21 April 2019 and Monday, 22 April 2019, subject to local timezone.|
|Look up yesterday in Wiktionary, the free dictionary.|
Philosophers have treated "yesterday" in various ways including as a relative but distinct concept of time. For example, John Locke in An Essay Concerning Human Understanding 1760 treated the concept of "yesterday" as follows:
I suppose, nobody thinks it conceivable that any thing does, or has existed in that future duration. Nor is it possible to join our idea of future duration with present or past existence, any more than it is possible to make the idea of yesterday, today, and tomorrow to be the same; or bring ages past and future together, and make them contemporary.
In Chinese philosophy also the meaning of "today" and "yesterday" is relative to contexts.
In the rhetoric of history "yesterday" can refer to the life framework of a past era, such as the example in literature of memory recalled from a previous, but now lost, lifestyle or society, such as recent colonial life.
Learning and language
The concepts of "yesterday", "today" and "tomorrow" are among the first relative time concepts acquired by infants. In language a distinctive noun or adverb for "yesterday" is present in most but not all languages, though languages with ambiguity in vocabulary also have other ways to distinguish the immediate past and immediate future. "Yesterday" is also a relative term and concept in grammar and syntax.
- Laurence C. Wu Fundamentals of Chinese philosophy 1986- Page 190 "We can also take this proposition as implying that the meaning of "today" and "yesterday" is relative to contexts. Yesterday was the today of yesterday, today is the tomorrow of yesterday, and tomorrow will be the today of tomorrow."
- Jaime Lane Wright Bodies of Evidence: The Rhetoric of Simulated History 054922520X 2007- Page 102 "The notion of yesterday, a longer moment in which objects and events were catalogued more particularly, demonstrates the closer, smaller framework against which memory is defined. The movement of Collective Memory recollection follows ..."
- Sarah De Mul Colonial Memory: Contemporary Women's Travel Writing 9089642935 2011 Page 12 "At the same time, the word “yesterday” translates colonial history into a vocabulary of a woman's everyday humdrum and orders colonialism into the chronology of her personal life. Although the conventional definition of “yesterday” denotes a .. Although the conventional definition of “yesterday” denotes a day that has finished, ... Dutch colonialism is not a political or diplomatic event in the past closed off at the moment of decolonisation, as conventional historiography would have it."
- Cath Arnold Child Development and Learning 2-5 Years: Georgia's Story 0761972994 1999 "She is referring, not only to her correct use of language, but to the concept of 'yesterday', which she uses correctly in this instance."
- Mary R. Key The Relationship of Verbal and Nonverbal Communication 3110813092 1980 p.20 "The consideration of time calls for communicating the concept of 'yesterday' and 'tomorrow'. In some languages the same term is used for both of these English words, though assuredly the people also have a way of dealing with past and future actions. For example, in Chama (Tacanan) mekawaxe means both 'yesterday' and 'tomorrow'. It is of interest that this same language group deals with space in a similar way. Thus, in Chama sam' means both 'left' and 'right';"
- The Function of tense in texts Jadranka Gvozdanović, Theodorus Albertus Johannes Maria Janssen, Östen Dahl - 1991 - Volumes 144 to 146 - Page 100 "Yesterday is relative to the day 'where we are', a minute ago to the minute, more or less, 500 years ago to 'our present' in a thematically suitable sense, perhaps 'this century', or 'modern times'. "