Bestselling author Jordan B. Peterson was deemed a “spam” threat this week by the moderators at Quora.

The famous clinical psychologist behind “12 Rules for Life” once answered a similar question on the California-based company’s website, but it disappeared Thursday under the rationale that it provides “little to no value” to readers.

“My 42 Rules Quora answer to the question ‘What are the most valuable things everyone should know?’ has been removed by the Quora admins,” he tweeted after the popular post was removed. “Here’s a screenshot of their rationale.”

Attached to the tweet was a screenshot by Quora’s user support team, which said: “Thank you for writing in. On Quora, spam is generally defined as one or more questions, answers, posts, comments, or messages whose purpose appears to be to direct traffic to external sites or solicit individual services, while providing little to no value back to the Quora community.”

The Quora employee, identified as James, then said that Mr. Peterson’s post may be considered “spamming” before he concluded: “After reviewing your content, we’ve determined that it was in violation of this policy and unfortunately, we will not be able to reinstate it.”

The decision comes less than six months since Whitcoulls, a large New Zealand bookstore, banned “12 Rules for Life” from its stores.

Whitcoulls explained the decision as one of prudence after the Christchurch massacre, although the psychologist’s book specifically addresses the Sandy Hook and Columbine massacres — and how to create the cultural conditions where fewer such tragedies occur.

The author’s supporters were not surprised by Quora’s decision. Some replies include:

“I think they are just testing new weapons to silence voices they don’t like.”

“Quora discouraging a clinical psychologist from posting on your site seems to be antithetical to what Quora stands for.”

“[This] guy is trying to help [people] for free and they shut him down. The upper crust elites are flexing their muscle to keep the masses ignorant.”

“The ministry of truth has declared you as a thought criminal.”

Fittingly, the author is currently creating a subscription-based “anti-censorship” platform called Thinkspot.

“Once you’re on our platform we won’t take you down unless we’re ordered to by a US court of law,” Mr. Peterson told podcasting star Joe Rogan on a June 9.