A reader this past week asked me about the choice I made in punctuating a sentence in a recent post. It’s an astute question, and will help us understand better the difference between a comma and a semicolon.
My post last week entitled Ing contrasted the present participle and the gerund, both of which end with the suffix –ing and are therefore often confused. I suggested that the admittedly somewhat technical topic can nonetheless yield practical choices for our revising, and for the last sentence of the piece I wrote: The whole topic repays close attention, such is the subtlety of our minds in the world. My reader asked (and a very close reader she is), shouldn’t the comma be a semicolon because you’re joining two independent clauses?
The question concerns the run-on sentence (a frequent problem I discussed in an earlier post, Running On and On), but something a little trickier is going on in the example at hand. To sort this out, let’s begin by reversing the order of the two clauses in order to see better what purports to be two independent clauses: Such is the subtlety of our minds in the world, the whole topic repays close attention. If this is indeed what the original version means to say, then the reader’s objection is very much in order and the comma should in fact be a semicolon: two independent clauses are connected with a semicolon, not a comma, when no conjunction is present to join them. In this design, the sentence would mean something like: The differences between a participle and a gerund which we have discussed reveal the subtlety of our minds, and the whole topic repays close attention. Just two independent thoughts stated together in one sentence and joined by the coordinating conjunction and.
But the original sentence could be (and is) saying something a little different. Let’s keep this reversed order for our analysis and change the conjunction: Such is the subtlety of our minds in the world that the whole topic repays close attention. Assuming the conjunction that (a subordinating conjunction) instead of and, we have created what is called a result clause. Result clauses are subordinate; they point to what results in light of what the main clause says, and that main clause must have some word that indicates degree (here the word such). In this design, the sentence would mean: So great is the subtlety of our minds that the whole topic repays close attention. We would have then a complex sentence that is pointing out the relationship, the logical connection, between the subtlety of our minds and the repaying of close attention. And notice, importantly, that there is neither a comma nor a semicolon in this version.
So now, if we restore the word order and return to our original version, The whole topic repays close attention, such is the subtlety of our minds in the world, we can see that it is to be read not as a compound sentence, but as a complex sentence with the result clause preceding the main clause. And so why the comma? Result clauses usually follow the main clause on which they depend, and when that order is reversed, as here, a comma is needed to alert the reader to that fact. This is an example of what is called an inverted sentence, whose reverse design is meant to emphasize the concluding idea.
How one reads the original sentence, whether as a compound or a complex sentence, depends in great measure on how one reads the word such, whether to mean of a certain kind or to such an extent. The word can denote either, and how we understand it here will determine the punctuation of the original sentence, be it right or wrong. Such, indeed, is the subtlety of language.