There are two senses in which writing can be good: it can sound good, and the ideas can be right. It can have nice, flowing sentences, and it can draw correct conclusions about important things. It might seem as if these two kinds of good would be unrelated, like the speed of a car and the color it's painted. And yet I don't think they are. I think writing that sounds good is more likely to be right.

The reason is that it makes the essay easier to read. It's less work to read writing that flows well. How does that help the writer? Because the writer is the first reader. When I'm working on an essay, I spend far more time reading than writing. I'll reread some parts 50 or 100 times, replaying the thoughts in them and asking myself, like someone sanding a piece of wood, does anything catch? Does anything feel wrong? And the easier the essay is to read, the easier it is to notice if something catches.

So yes, the two senses of good writing are connected in at least two ways. Trying to make writing sound good makes you fix mistakes unconsciously, and also helps you fix them consciously; it shakes the bin of ideas, and also makes mistakes easier to see. But now that we've dissolved one layer of preposterousness, I can't resist adding another. Does sounding good do more than just help you get the ideas right? Is writing that sounds good inherently more likely to be right? Crazy as it may seem, I think that's true too.

An essay is a cleaned up train of thought, in the same way dialogue is cleaned up conversation, and a train of thought has a natural rhythm. So when an essay sounds good, it's not merely because it has a pleasing rhythm, but because it has its natural one. Which means you can use getting the rhythm right as a heuristic for getting the ideas right. And not just in principle: good writers do both simultaneously as a matter of course. Often I don't even distinguish between the two problems. I just think Ugh, this doesn't sound right; what do I mean to say here?

Ok, many people will be thinking, this seems plausible so far, but what about liars? Is it not notoriously possible for a smooth-tongued liar to write something beautiful that's completely false?

So it's not quite right to say that better sounding writing is more likely to be true. Better sounding writing is more likely to be internally consistent. If the writer is honest, internal consistency and truth converge.

Indeed, the two senses of good writing are more like two ends of the same thing. The connection between them is not a rigid one; the goodness of good writing is not a rod but a rope, with multiple overlapping connections running through it. But it's hard to move one end without moving the other. It's hard to be right without sounding right.