A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the degree is most often abbreviated PhD (or, at times, as Ph.D. in North America) and is pronounced as three separate letters ( ).
PhDs are awarded for programs across the whole breadth of academic fields. Since it is an earned research degree, those studying for a PhD are required to produce original research that expands the boundaries of knowledge, normally in the form of a dissertation, and, in some cases, defend their work before a panel of other experts in the field. In many fields, the completion of a PhD is typically required for employment as a university professor, researcher, or scientist.
Definition In the context of the Doctor of Philosophy and other similarly titled degrees, the term "philosophy" does not refer to the field or academic discipline of philosophy, but is used in a broader sense in accordance with its original Greek meaning, which is "love of wisdom". In most of Europe, all fields (including history, philosophy, social sciences, mathematics, and natural philosophy – later known as natural science) other than theology, law, and medicine (the so-called professional, vocational, or technical curricula) were traditionally known as philosophy, and in Germany and elsewhere in Europe the basic faculty of liberal arts was known as the "faculty of philosophy".'What is Liberal Arts? Definition, Scope, History & Importance' . 10 June 2025. O. P. Jindal Global University. Chhattisgarh.Faculty of Philosophy . Heidelberg University. Germany.Faculty of Philosophy. University of Strasbourg. France.Faculty of Philosophy . University of Barcelona. Spain.
A PhD candidate must submit a project, thesis, or dissertation often consisting of a body of original academic research, which is in principle worthy of publication in a peer-reviewed journal. In many countries, a candidate must defend this work before a panel of expert examiners appointed by the university. Universities sometimes award other types of doctorate besides the PhD, such as the Doctor of Musical Arts (DMA) for music performers, Doctor of Juridical Science (SJD) for legal scholars and the Doctor of Education (EdD) for studies in education. In 2005 the European University Association defined the "Salzburg Principles", 10 basic principles for third-cycle degrees (doctorates) within the Bologna Process. These were followed in 2016 by the "Florence Principles", seven basic principles for doctorates in the arts laid out by the European League of Institutes of the Arts, which have been endorsed by the European Association of Conservatoires, the International Association of Film and Television Schools, the International Association of Universities and Colleges of Art, Design and Media, and the Society for Artistic Research.The specific requirements to earn a PhD degree vary considerably according to the country, institution, and time period, from entry-level research degrees to higher doctorates. During the studies that lead to the degree, the student is called a doctoral student or PhD student or a research scholar; a student who has completed any necessary coursework and related examinations and is working on their thesis/dissertation is sometimes known as a doctoral candidate or PhD candidate. A student attaining this level may be granted a Candidate of Philosophy degree at some institutions or may be granted a master's degree en route to the doctoral degree. Sometimes this status is also colloquially known as "ABD", meaning "all but dissertation". PhD graduates may undertake a postdoc in the process of transitioning from study to academic tenure.
Individuals who have earned the Doctor of Philosophy degree use the title Doctor (often abbreviated "Dr" or "Dr."), although the etiquette associated with this usage may be subject to the professional ethics of the particular scholarly field, culture, or society. Those who teach at universities or work in academic, educational, or research fields are usually addressed by this title "professionally and socially in a salutation or conversation". Alternatively, holders may use post-nominal letters such as "Ph.D.", "PhD", or "DPhil", depending on the awarding institution. It is, however, traditionally considered incorrect to use both the title and post-nominals together, although usage in that regard has been evolving over time.
History Medieval and early modern Europe The first doctoral degree was awarded at the University of Paris around 1150. In the universities of Medieval Europe, study was organized in four faculties: the basic faculty of arts, and the three higher faculties of theology, medicine, and laws (canon law and civil law). The doctorates in the higher faculties were quite different from the current PhD degree in that they were awarded for advanced scholarship, not original research. No dissertation or original work was required, only lengthy residency requirements and examinations.
All of these faculties awarded intermediate degrees (bachelors of arts, theology, laws and medicine) and final degrees. Initially, the titles of master and doctor were used interchangeably for the final degrees—the title Doctor was merely a formality bestowed on a Teacher/Master of the art—but by the late Middle Ages the terms Master of Arts and Doctor of Theology/Divinity, Doctor of Law, and Doctor of Medicine had become standard in most places (though in the German and Italian universities the term Doctor was used for all faculties).Ruano-Borbalan, Jean-Claude. (23 July 2022). Doctoral education from its medieval foundations to today's globalisation and standardisation. Wiley (publisher) online library.
Besides these degrees, there was the licentiate. Originally this was a license to teach, awarded shortly before the award of the master's or doctoral degree by the diocese in which the university was located, but later it evolved into an academic degree in its own right, in particular in the continental universities.
The full course of studies might, for example, lead in succession to the degrees of Bachelor of Arts, Licentiate of Arts, Master of Arts, or Bachelor of Medicine, Licentiate of Medicine, or Doctor of Medicine, but before the early modern era, many exceptions to this existed. Most students left the university without becoming masters of arts, whereas regulars (members of monastic orders) could skip the arts faculty entirely.
Educational reforms in Germany This situation changed in the early 19th century through the educational reforms in Germany, most strongly embodied in the model of the University of Berlin, founded in 1810 and controlled by the Prussian government. The arts faculty, which in Germany was labelled the faculty of philosophy, started demanding contributions to research, attested by a dissertation, for the award of their final degree, which was labelled Doctor of Philosophy (abbreviated as Ph.D.)—originally this was just the German equivalent of the Master of Arts degree. Whereas in the Middle Ages the arts faculty had a set curriculum, based upon the trivium and the quadrivium, by the 19th century it had come to house all the courses of study in subjects now commonly referred to as sciences and humanities. Professors across the humanities and sciences focused on their advanced research.
These reforms proved extremely successful, and fairly quickly the German universities started attracting foreign students, notably from the United States. The American students would go to Germany to obtain a PhD after having studied for a bachelor's degree at an American college. So influential was this practice that it was imported to the United States, where in 1861 Yale University started granting the PhD degree to younger students who, after having obtained the bachelor's degree, had completed a prescribed course of graduate study and successfully defended a thesis or dissertation containing original research in science or in the humanities.See, for instance, In Germany, the name of the doctorate was adapted after the philosophy faculty started being split up − e.g. Dr. rer. nat. for doctorates in the faculty of natural sciences − but in most of the English-speaking world the name "Doctor of Philosophy" was retained for research doctorates in all disciplines.
The PhD degree and similar awards spread across Europe in the 19th and early 20th centuries. The degree was introduced in France in 1808, replacing diplomas as the highest academic degree; into Russia in 1819, when the Doktor Nauk degree, roughly equivalent to a PhD, gradually started replacing the specialist diploma, roughly equivalent to the MA, as the highest academic degree; and in Italy in the 1980s, when PhDs gradually started replacing the Laurea as the highest academic degree.
History in the United Kingdom
Research degrees first appeared in the UK in the late 19th century in the shape of the Doctor of Science (DSc or ScD) and other such "higher doctorates". The University of London introduced the DSc in 1860, but as an advanced study course, following on directly from the BSc, rather than a research degree. The first higher doctorate in the modern sense was Durham University's DSc, introduced in 1882.
This was soon followed by other universities, including the University of Cambridge establishing its ScD in the same year and the University of London transforming its DSc into a research degree in 1885. These were, however, very advanced degrees, rather than research-training degrees at the PhD level. Harold Jeffreys said that getting a Cambridge ScD was "more or less equivalent to being proposed for the Royal Society."
In 1917, the current PhD degree was introduced, along the lines of the American and German model, and quickly became popular with both British and foreign students. The slightly older degrees of Doctor of Science and Doctor of Literature/Letters still exist at British universities; together with the much older degrees of Doctor of Divinity (DD), Doctor of Music (DMus), Doctor of Civil Law (DCL), and Doctor of Medicine (MD), they form the higher doctorates, but apart from honorary degrees, they are only infrequently awarded.
In English (but not Scottish) universities, the Faculty of Arts had become dominant by the early 19th century. Indeed, the higher faculties had largely atrophied, since medical training had shifted to teaching hospitals,C. Singer and S.W.F. Holloway, Early Medical Education in England in Relation to the Pre-History of the University of London, Med Hist. 1960 January; 4(1): 1–17. the legal training for the common law system was provided by the Inns of Court (with some minor exceptions, see Doctors' Commons), and few students undertook formal study in theology. This contrasted with the situation in the continental European (and Scottish) universities at the time, where the preparatory role of the Faculty of Philosophy or Arts was to a great extent taken over by secondary education: in modern France, the Baccalauréat is the examination taken at the end of secondary studies. The reforms at the Humboldt University transformed the Faculty of Philosophy or Arts (and its more recent successors such as the Faculty of Sciences) from a lower faculty into one on a par with the Faculties of Law and Medicine.