The
first clue is that the introverted type infp
loves all living creatures. Dr. Doolittle was undoubtedly
an infp, as were Dr. Albert Schweitzer and Princess Diana.
That's Nancy on the right getting in "touch" with
the mule.
Susan, the enfp extrovert, is facing toward the camera. She's
excited, striking a pose and ready to lead the parade! Nancy,
the introvert, is "lost" in her experience with
the mule.

Here
the twins pose for a formal portrait. Susan, the enfp extrovert
pulls forward toward the camera, her eyes engaging the photographer.
With her right hand she holds on to her sister who is resiting
the touch. Look at their hands. It is very revealing. Introverts
are territorial about their own bodies and often don't like
to be touched without permission!
Nancy,
the infp introvert on the left, pulls away from the camera
and draws her attention inward, though she has a friendly
look on her face.
Did
you guess correctly?