哲学博士学位的程度表明，持有人进行了相当大的原创性研究，该研究由持有人在适当的学术监督下和规定的研究环境下进行并报告。博士学位论文证明了候选人领域的权威，并显示了相关领域知识掌握的证据。它表明候选人全面掌握了适当的方法论技巧，并意识到其局限性。论文对知识也做出了独特的贡献。它对知识的贡献取决于方法的新颖性和/或对发现的解释，在某些情况下还包括发现新事实。论文展示了在专业领域和国际背景下有效交流研究结果的能力。这是一项仔细，严格和持续的工作，表明一项研究“学徒制”已经完成，持有人被接纳为该学科领域的学者。
The degree of Doctor of Philosophy signifies that the holder has undertaken a substantial piece of original research, which has been conducted and reported by the holder under proper academic supervision and in a research environment for a prescribed period. The PhD thesis demonstrates authority in the candidate's field and shows evidence of command of knowledge in relevant fields. It shows that the candidate has a thorough grasp of the appropriate methodological techniques and an awareness of their limitations. The thesis also makes a distinct contribution to knowledge, which rests on its originality of approach and / or interpretation of the findings, and, in some cases, the discovery of new facts. Additionally, the thesis demonstrates an ability to communicate research findings effectively in the professional arena and in an international context. It is a careful, rigorous, and sustained piece of work demonstrating that a research 'apprenticeship' is complete and that the holder is admitted to the community of scholars in the discipline. In scope, the PhD thesis differs from a research Masters thesis chiefly by its deeper and more comprehensive treatment of the chosen subject. It is written succinctly, in English, unless approval has been given for the thesis to be written in a language other than English. The normal length of a PhD thesis is 80,000 words, exclusive of words in tables, maps, bibliographies and appendices. Footnotes are included as part of the word limit.