Contemplative traditions and meditative disciplines often describe thoughts as sticky. One thought glues itself to some other vaguely related thought that happens to come along, and before you know it, you’re stuck fast in a gooey and unshapely conceptual world of your own making, a ramble that takes you far from the simple, wise, and self-evident truth of things as they really are. In meditation, this is named the work of the ego; in the craft of writing, this unconnected elaboration of thought is called discursive prose.
Rhetorical traditions and academic disciplines, on the other hand, are all about the progressive development of a conception, the methodical construction of a logical connection between one thought and the next in a type of writing called expository. Expository prose explains things; it begins somewhere, ends somewhere, and has a reason for going there. If in discursive prose thoughts are sticky, catching any idea in the air around them, in expository prose they are cohesive, each being designed and suited for the next thought made to follow. Instructively, the adjectives cohesive and coherent are linguistically related.
Here is an example of discursive prose: I’m planning a trip to California this winter. I have a lot of projects to finish at home this summer. I am going to build a new patio, the old cement tiles there now have cracked over the years, expand my garden so that I can grow my own vegetables and save some money at the grocery store, and I have to generally fix things up around the house. I’ll need a well-deserved vacation. Notice the tone or manner of the passage: it has all the character of someone thinking aloud, someone thinking off the top of his head and following whatever idea next happens to arrive. The idea of the first sentence, planning a trip to California, is not addressed again until the last sentence of the passage. Between those two, there is a cluster of ideas which presumably have to do with the writer’s deserving a vacation (the predicate of the last sentence), but they do not cohere through structure, punctuation, or the arrangement of words. Just as often in casual conversation, we are left to find the connection to the thesis announced in the first sentence.
By contrast, here is an expository version of the same passage: I’m planning a trip to California this winter to give myself a well-deserved vacation. I will have finished a lot of projects at home this summer—replacing the old cement tiles on my patio, planting vegetables in the garden to save some money at the store, and caulking and painting some windows around the house. Observe first how more concise this passage is (trimmed by almost 25%, in fact), and notice too the more deliberately constructed sentence structure. The first sentence here combines the first and last of the discursive version, and the balance of the passage—one sentence—is more accurate in tense (note the future perfect will have finished), concisely specific in detail (combining the two clauses of the second sentence into one), and interesting in sentence design (parallel structure with an energetic dash to mark the examples of the projects to be finished).
Expository prose, then, is disciplined discursive prose. Discourse, which means conversation or talk, gives us the adjective discursive, and just like conversation, discursive prose often goes in all directions helter-skelter in an attempt to bring someone else into its orbit of ideas. And also like conversation, the term discursive can ambiguously mean either rambling talk or coherent comment. If we can remember though that coherence best serves our attempts to represent the ideas we have in mind, we can avoid then the censure of sticky thoughts and compose prose that is coherent and fitted to the task at hand.
***