For years, Facebook has resisted adding a Dislike button on its social network, but that doesn't mean Mark Zuckerberg isn't "thinking" about it.

In his second public question-and-answer session held at the company headquarters in Menlo Park, California and livestreamed over the Q&A with Mark Facebook events page, the 30-year-old founder and CEO said Facebook is considering adding something akin to a Dislike button, not an actual Dislike button per se.

"We're thinking about it, on the Dislike button," he said. "It's an interesting question."

Zuckerberg agreed that a Dislike button would be appropriate in certain instances, such as when someone expresses grief over the death of a loved one or when another user shares a link to a natural disaster news story and liking the posts doesn't exactly seem proper.

He also said that he didn't want a Dislike button to be used for the wrong reasons and sow negativity for Facebook users. While having a Like button is "really valuable" because it allows users to express positive emotions, a Dislike button, Zuckerberg said, is not "good for the world."

"I don't think there needs to be a voting mechanism about whether posts are good or bad," he said. "I don't think that's socially very valuable or good for the community to help people share the important moments in their lives."

He did, however, acknowledged that users need to be able to express a broader range of emotions apart from the positive sentiments that come with the like button. Some people say they can just comment to express a negative sentiment, but even Zuckerberg agrees that commenting is not as simple as pressing the Dislike button or whatever Facebook might think of in its place.

"We need to figure out the right way to do it so it ends up being a force for good, not a force for bad and demeaning the posts that people are putting out there," he said. "We don't have anything that's coming out soon but it's an important area of discussion."

This isn't the first time Zuckerberg hinted at something like a Dislike button. In 2010, he told CNN's Diane Sawyer that a Dislike button "is something that we definitely would think about." He added that many users seemed to be clamoring for such a button, and that Facebook listens to all user suggestions.

However, Zuckerberg made it clear Facebook isn't likely to roll out a dislike mechanism anytime soon, and the likely reason for that is that having people thumbing down brands' posts is not good for business for both Facebook and online marketers. Businesses are not going to rush to Facebook to market their products and services if Facebook will allow users to spread negativity about them.