Someone once said to me that the perfect research essay would be one sentence long and the rest would be a single footnote.
I have no idea what they were drinking that night. I think they were having a go at the desperation some students have to slather everything in a think butter of footnotes such that the actual text of the essay virtually disappears.
It is worth just clarifying what footnotes are there for. The chief purpose of them is to serve as a place to put your references. It is an efficient way of showing that your statements rest on the authority of someone else and that you have researched your essay well. Of course, the Author-Date system asks you to put your references in brackets in the text, so footnotes won’t have that function then.
Do take care to make it clear how the reference relates to the text. If you’ve put a reference in at the end of the sentence ask yourself: what is it doing there? Is it that the author I am citing agrees with this point? Or disagrees? Or – well, what? A couple of short words can do the job here. Put a ‘so’ in front of the reference, for example, and you have indicated that the author concurs, and the reader knows exactly what the reference I demonstrating.
One other use of footnotes is to provide a bit of butt cover. What do I mean? Indicate by means of a footnote where there are unexplored avenues. Let the reader know that you are aware of tracks you might have followed, but chose not to. Protect yourself from the flank attack – the attack which says ‘weren’t you aware of Augustine’s views on the subject?’
Another purpose of footnotes is to provide interesting but non-essential commentary. Now you need to take great care here – don’t put something actually creative and vital in your footnotes that should be in the text. I say to my research students whenever I see an extended footnote ‘shouldn’t this be in the text?’ The footnote may be a sign of simple indecision on your part. If that’s the case – decide!
A teacher of mine used to say ‘footnotes should be fun’. I don’t think he meant that this was the place to put a couple of jokes you have lately heard. Rather – if you have a genuinely interesting diversion, then this is the place for it.
But remember: don’t try to hide, or look as if you are trying to hide, extra words in the footnotes. Most institutions will ask you to count footnotes in your final word count in any case.