Writing is thinking.

Writing is not a process simply of transcribing ideas that are already worked out in full. Writing is the process of working through those ideas.

It is not necessary, nor is it likely even desirable, to sit down and write only after your ideas are worked out, because the very act of writing is the most important part of the process of working them out in full.

Writing is thinking.

I'm not telling you this, because you probably already know it. I'm telling it to myself. When my writing is going well and steadily, I seem to know this instinctively. But when I'm trying to find my way back in after a time away, I always want to have every i dotted in my head before I start writing.

Nope, doesn't work that way. Writing is thinking. Thinking is not writing.