title: rspec failing error: expected false to respond to `false?`
body: <p>I am running this portion of a test:</p>
  
  <pre><code> describe Dictionary do
     before do
       @d = Dictionary.new
     end
  
      it 'can check whether a given keyword exists' do
          @d.include?('fish').should be_false
        end
  </code></pre>
  
  <p>With this code:</p>
  
  <pre><code>class Dictionary
    def initialize
      @hash = {}
    end 
  
    def add(new_entry)
      new_entry.class == String ? @hash[new_entry] = nil : new_entry.each { |noun, definition| @hash[noun] = definition}    
    end 
  
    def entries
      @hash 
    end 
  
    def keywords
      @hash.keys
    end
  
    def include?(word)
      if @hash.has_key?(word)
        true
      else 
        false
      end 
    end 
  end 
  </code></pre>
  
  <p>I don't know what I'm doing wrong, but my tests keep failing and saying this: </p>
  
  <pre><code>&gt; 1) Dictionary can check whether a given keyword exists
  &gt;      Failure/Error: @d.include?('fish').should be_false
  &gt;        expected false to respond to `false?`
  </code></pre>
  
  <p>I am confused at the error since it seems to be giving the correct answer. I would really appreciate if someone could take a few minutes to tell me what's wrong with my code. 
  Thank you tons. </p>