Your brain is for processing and not for storage. It's a CPU and not a HDD. Only when you free your mind from the storage, you will have time to think. So we use second brains to store what we think and not care of remembering it.
Writing is a great to find insight and gathering all your thoughts. Second brains help you store all of it.
You will be amazed with the new connections you will find when you maintain this. Your thoughts will be served back to you.
Organising is difficult though. Roam especially does a great job at this. It is made for these purposes. With the bi directional linking it makes it easy for us find connections and references to what we have.
How can you make your second brain public? - this website!
I do it using
gatsby-theme-andy which is a gatbsy theme on top of
gatbsy-theme-brain. It recognises the internal links that have the double backticks Roam syntax and puts in the references. If a note is referred in other notes, it gets added below the note in the list of references. I wrote about the story of how I built this.