polymorphic associations

Ok, I've been on this issue for several hours already. If someone with
more RoR experience can help me out. It will be much appreciated.

A small description of what I am trying to do. In the deal show view.
I want to display comments for a particular deal. So far everything
works, except that I am unable to list down the comments. I can submit
comments without any problems.

Here is my code:

social migration:

class CreateSocials < ActiveRecord::Migration
  def self.up
    create_table :socials do |t|
      t.references :user
      t.references :deal
      t.references :entity, :polymorphic => true
      #t.references :commentable, :polymorphic => true

      t.timestamps
    end
  end

  def self.down
    drop_table :socials
  end
end

For those who are wondering. I need the social table class, to keep
track of user interactions. An interaction can be comment, upload,
like, etc. I need this table, because in the future I will have a page
that displays recent user interactions sorted by created_at