First-time essay writers at the college level are sometimes unsure of the proper use of sources. The general rules are:
(i) The wording you use must be your own and not copied or even loosely paraphrased from another work. Any wording not your own must be represented as a quote by enclosing it in quotation marks (if it is less than three lines of text) or setting it off as an indented block of text (if it is more than 3 lines of text), both with appropriate footnoting.
(ii) The source of ideas which are sufficiently novel or idiosyncratic not to be taken as commonly known must be indicated either in the text or in a footnote as is appropriate. The same holds of any detailed account of one theory or another.
The most likely problem with (ii) is that you take it too seriously and footnote every sentence. The satisfaction of (ii) must be tempered by the need to retain a clean and uncluttered text.
The real danger lies in (i); its violation is a serious form of plagiarism and is treated as a serious offence within the university and academia in general. Here is an example to make the requirements of (i) clear:
The original text says:
In astronomy, the half century from 1570 to 1620 saw a radical break with tradition. In mechanics, there was no such sharp discontinuity.
You are guilty of plagiarism if your text reads:
...and we can date the start of the scientific revolution to Copernicus' death in 1543. In astronomy, the half century from 1570 to 1620 saw a radical break with tradition. In mechanics, there was no such sharp discontinuity.6 Nevertheless ...
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6. Toulmin and Goodfield, op.cit., p.210.
Note that the presence of the footnote to your source makes no difference since there are no quotation marks. You are still guilty of plagiarism if you loosely paraphrase your source text. For example:
...and we can date the start of the scientific revolution to Copernicus' death in 1543. The fifty years from 1570 to 1620 saw a radical break with tradition in astronomy. However in mechanics, there was no such sharp discontinuity. Nevertheless ...
To be free of plagiarism, you would need to present the sentences as follows:
...Toulmin and Goodfield note the differences in development:6 "In astronomy, the half century from 1570 to 1620 saw a radical break with tradition. In mechanics, there was no such sharp discontinuity." Nevertheless...
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6. Toumin and Goodfield, op.cit., p.210.
Quoting the sentence in this way would free you of a charge of plagiarism. But that does not make this style of quotation good writing. You should not litter your essay with quotes simply to avoid a charge of plagiarism. In general there are only two reasons to quote in an essay:
(a) The passage in question is an essential part of a critical text whose wording is to be analyzed.
(b) You feel you must reassure the reader that the person in question really did say what you claim was said.
A writer who presents quotes for reasons other than (a) and (b) is usually a writer who is in trouble. Very commonly, writers with this trouble begin sentences in their own words but then complete the sentences with quotations. For example:
The publication of Copernicus' theory in 1543 was a landmark in the history of science and "in astronomy, the half century from 1570 to 1620 saw a radical break with tradition."6
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6. Toumin and Goodfield, op.cit., p.210.
This style of quotation is a characteristic of bad essays and you should never use it. Unfortunately, there is no easy solution for a writer with this problem. If you frequently feel the need to quote merely because the text you are reading says it better than you can, you should recognize this as a danger sign. You are probably working too closely to your sources and should rethink exactly what you are trying to achieve. Your task ought to be primarily one of critical analysis not exposition in the essay. You should be one step removed from the source in question, reflecting critically on its contents and seeing how it fits with the point you are trying to make. Your task is not the transferring of information in "cut and paste" fashion from your sources.
John D. Norton, Department of History and Philosophy of Science, University of Pittsburgh