'Proof of brain' is one of the original unique design factors that peaked interest in Steem's design... But today it is mostly broken due to bid bots - let's look at it more closely and explore what might be done to improve the situation.
If posts that meet real needs are meant to be the highest valued and one of our real needs is to be able to identify the posts that most meet real needs - then maybe posts that help is reach that goal are the MOST important posts there are?
There's a reason why Facebook's designers have aligned their system's algorithms to reward engagement (likes, comments and shares etc.) with extra reach in the network - it's basically because they want to expand Facebook's userbase and keep it relevant. To do this, they know they need to keep the users interested and excited to keep using the system and that means finding ways of allowing them to discover content they like on a regular basis. Content that generates a lot of comments, likes/votes and shares/resteems is inherently interesting in some way - so it makes sense that as long as those who game the system are kept in check somehow, on average, if highly engaged content is made visible to others then it will be appreciated by more users than low engaged content will be.
Steem doesn't have the AI managed and curated system that Facebook does and that is actually one of it's strengths. While a generic algorithm that learns preferences and determines what users will see and won't see 'could' be useful to everyone, the truth is that Facebook is a corporation (and most likely an arm of the 'intelligence' services), so it's integrity is always going to be low in this regard. Aside from outright censorship, Facebook is well known to have a tendency to try to promote itself as some kind of authority for what is 'true' and thus the reach of ideas they deem to be 'untrue' tends to be hampered. I don't know about you, but I don't really need or want the postal service to read through all my mail and just fail to deliver some if they decide it doesn't contain enough truth! What Steem does have is 'Proof of brain' - which is, in essence, the system of users rewarding the 'best' content with upvotes.. The proof of the brain is meant to be in that people appreciate the content and thus some brain must be present in it's creation.
Setting aside the reality that not everyone's brain is the same or shares the same ideals and that stake weighted voting means that not all votes are equal, this mechanism does at least have the strength that it allows the community to operate as a whole, promoting and demoting content according to something tangible and defined. When groups of creative people come together in a shared vision - such as the somewhat abstract idea of 'making great content', there tends to be a team atmosphere where individuals aim to fulfill real needs of other people. This is, to me, part of the power of 'proof of brain', in that it is also to some extent 'proof of understanding real needs'.
REAL Needs? Bid bots are an affront to community spirit.
Sadly, this is where proof of brain and Steem are falling down most at the moment, to my mind. Before bid bots were a thing, the trending pages were a decent reflection of content that was varied and interesting, but which could be relied on to some extent to be a clear solution to someone's questions, desires, problems and real needs on some level. I might not personally want to know how to make the perfect CV or know the perfect mechanics of a paper airplane, but at least if I see a well made post on that subject on the trending page when it has gotten there organically, I know that someone, somewhere DOES want to see it.
As long as votes are for sale and proof of brain is broken, all of these other strengths disappear too. Now posts don't need to meet anyone's real needs to have the highest reach, they only need to have been made by someone willing to pay someone else a high enough amount of money. The entire creative kick and magic of community co-creativity has been shat on from a great height in one fell swoop!
The fact is that there are so many posts on Steem that we really NEED a mechanism for exposing the best ones and the community has always been intended to manually power that process.
I truly am saddened that so many in the community fail to understand this basic dynamic and have no problem with facilitating a centralisation of power into the hands of those who operate the bid bots here. I feel this is a reflection of the dynamic we see offline too, where predatory 'business' people exploit creative community intent at every opportunity and hide behind carefully crafted PR messages in order to deceive as many as possible into using their products.
So what is the solution?
Thankfully, a few Steem sites already filter out posts that are boosted by bid bots, including 
It is also an option to have the community rally around the path of integrity, such that we downvote posts that use bid bots en mass. It wouldn't necessarily take more than a minority amount of downvoting cost to put people off of using the bots as their profit margins are already slim.
I imagine we will see this issue tackled in creative ways by the new Steem foundation, but that, to some extent depends on bot operators not having the power position within it. I suggest learning who is involved and not supporting those who may corrupt the potential for positive change here!
Wishing you well,
Ura Soul
I am currently among the top 100 in the Steem User Authority Table
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