Plagiarism is defined by the University as submitting as one's own work, irrespective of intent to deceive, that which derives in part or in its entirety from the work of others without due acknowledgement. It is both poor scholarship and a breach of academic integrity.
You are obliged to have read and understood the University’s policy on plagiarism which is given at http://www.admin.cam.ac.uk/univ/plagiarism/students/statement.html. Here you will find the University’s guidelines on plagiarism, how to avoid it, what will happen if plagiarism is suspected, and what will happen if plagiarism has occurred.
If you present as your own ideas those which are in fact drawn from the work of others, you run the risk of being penalised by the examiners, as well as being disciplined by the University. The Faculty is aware that some students are initially unclear as to what constitutes fair and unfair use of the work of other: here follows some guidance on the subject. Students from other academic traditions should be aware that there may be differences in the approach to academic writing with which they are familiar, and those expected in Cambridge, where you are expected to be explicit when acknowledging all sources whether paraphrased or quoted.
The problem of plagiarism relates to all types of written work, including essays written for term-time supervisions. In fact, it is through writing of supervision essays that most undergraduates quickly come to appreciate the extent to which earlier work in a particular field should be explicitly acknowledged. Supervisors will routinely advise their pupils whether they are giving adequate recognition to the ideas formulated by other scholars which are being reported in their essays. On common sense grounds, it is clearly safer to be over-scrupulous in attributing other writers’ ideas than to be too sparing in making acknowledgements. The experience of attending lectures and reading academic books and articles will also help to demonstrate in detail how established scholars acknowledge the contribution of their predecessors in the field.
The possibility of plagiarism (taking the ideas or writing of another person and using them as one’s own) should be borne in mind particularly when writing an essay which will form part of Tripos or MPhil assessment, and when writing Tripos, MPhil or PhD dissertations. You will be expected to have a solid grasp of existing publications relevant to the topic, but the work that you submit must be your own, except where the contributions of others are acknowledged. Consequently it is essential when you are working on, and writing up, your thesis to be extremely careful to distinguish your own ideas from those of others, and to show by means of footnote references (and quotation marks, when you are using an author’s own words) occasions when you are alluding to someone else’s work. In any case, you should be aiming to ‘make the argument your own’ by using your own words and providing your own judgements on the other authors’ views, rather than following closely someone else’s argument and examples. Likewise, when referring to ancient authors or documents, you should add references in the footnotes, so the reader can find the passage in question: you are required by the Regulations to ‘give full references to sources’. If you use a printed English translation, you should also acknowledge its source (eg Loeb translation).
If you have concerns about any of these issues, you should consult your supervisor at an early stage. Undergraduates can also consult their Directors of Studies, or the Academic Secretary (Undergraduate). Graduates can also consult the Academic Secretary (Graduate).