We have a tendency to think in incomplete sentences. If there was some way to put our thinking into words and then project those words onto a blank wall in front of us, our thoughts would be illegible. We would not find fully-formed sentences but instead something more akin to sentence fragments. Our thoughts would read like shattered glass. This is why writing is so important. Writing forces us to do the hard work of thinking in complete sentences, of figuring out our thoughts. If our thinking is sloppy in our heads, it will appear sloppy on the page. And so the practice of clear writing leads to clearer thinking and vice versa.