As already explained above he has to become a member if he wants to participate in that by commenting.
In article section there is a facility for the guests to comment. So if you send a link of your or any article to others, they can submit their comment there without becoming the member.
Knowledge is power.
Beware! I question everything and everybody.
When you make a commitment, you create hope. When you keep a commitment you create trust! ~ John C. Maxwell
It helped me to understand that ISC allows to share our writings. Now, I can share the write-ups.
'Any fool can know. The point is to understand."- Albert Einstein