1: ...
 [by parsing <frames.n3>]

2: <http://notes.restdesc.org/2013/frames/Frame1> a :VideoFrame .
 [by erasure from step 1]

3: @forAll :frame . { :frame a f:VideoFrame . } log:implies {:frame a f:Image . } .
 [by erasure from step 1]

4: ...
 [by rule from step 3 applied to steps [2]
  with bindings {'frame': u'<http://notes.restdesc.org/2013/frames/Frame1>'}]

5: <http://notes.restdesc.org/2013/frames/Frame1> a :Image .
 [by erasure from step 4]

6: ...
 [by parsing <query.n3>]

7: @forAll :x . { :x a f:Image . } log:implies {:x a f:Image . } .
 [by erasure from step 6]

8: <http://notes.restdesc.org/2013/frames/Frame1> a :Image .
 [by rule from step 7 applied to steps [5]
  with bindings {'x': u'<http://notes.restdesc.org/2013/frames/Frame1>'}]

     @prefix : <http://notes.restdesc.org/2013/frames/frames#> .
    
    <http://notes.restdesc.org/2013/frames/Frame1>     a :Image .