Are Comments and Posts the same

I'm currently in the process of building another generic Blog style website, and I got to thinking. Where I usually use a separate table for Posts and another for Comments and then join them using FK's. I began to wonder, are they really worthy of separate tables?

For example properties they both share include:

• ID (int)
• Title (string)
• Body (text)
• Poster (FK)
• Created At (Datetime)
• Updated At (DateTime)
• Likes/Dislikes(ints)
• Etc..

One Post Has(optional) Many Comments,Many Comments have one Post, but also One Comment, may also have many Comments.

Now would it make more sense. For a table to contain both, Comments and Posts, and self reference them from within? Having a separate lookup table for containing what each type of entity is.

Then however, if a Post is a Comment, and a comment is no different to a post. Except for in a view context, should posted Images also be contained within the same table? As these to, can have likes/comments/name etc.

Question in short: Do blog Posts and Comments belong in the same table?