The way a "like" works is thus:
1. User likes a post.
2. On a like, the "like" number of the author is increased by one.
End.
The way an "unlike" works is thus:
1. User "unlikes" their previous like.
2. The "like" number of the author is decreased by one (as the like is removed from their post).
End.
A user cannot unlike a post they haven't previously liked. We cannot keep the number static if someone dislikes the post, as they could re-like the post and increase the number indefinitely.
It does not "like" a user like the stars system does, it does not "like" a topic like the stars system does. It likes posts, it loves posts, posts are its bread and butter.
End.
