Writing as ideation
Writing helps me focus on creating new ideas. Things never look as clear in my head as when I write them down.
In my head concepts seem more clear than they really are. Like in a dream, I believe I understand things better than I do. I miss connections, I make assumptions, and my arguments have gaps I overlook entirely.
When I force myself to write things down I realize how little I know.
Removing judgment from writing allows the truth to come out. Some truths are too ugly so we keep them deep in our minds. Writing can help expose those.
Silencing the inner critic (as when done for writing for meditation or therapy) is a good practice even when writing for others. It allows for ideas to surface before they can be killed by doubt. Criticizing is easy and young ideas are fragile.
Writing clears my mind and helps put my ideas in order. When I am stuck, nothing helps as much as starting writing.