> You glean just as much information from someone clicking Like and leaving no context as you do someone clicking Dislike and leaving no context.
I disagree; Perhaps a programming analogy instead?
if(x == 0) # when this is true, you know what x is, and what it isn't
if(x != 0) # when this is true, you only know what x isn't
Like with no context tells the receiver what the audience wants (more of the same); dislike doesn't (okay, so don't do this thing, but do what instead?).
That's what I mean by the analogy - "do this" is a much more useful statement than "don't do that".