Why self?

selfExample.rb

class Animal
  attr_accessor :name

  def initialize(name)
    @name = name
  end

  def eat(other)
    puts "#{@name} ate #{other.name}! #{self.noise}"
  end
end

class Human < Animal
  attr_accessor :catchphrase

  def initialize(name, catchphrase)
    super(name)
    @catchphrase = catchphrase
  end

  def noise
    @catchphrase
  end
end

a = Human.new("Adam", "Right on!")
b = Animal.new("Chicken")
a.eat(b)
#=> "Adam ate Chicken! Right on!"