introspection

up and down

     and through

          and through

     up and down

and through

     and through

          up and down

     and through

and through

     up and down

          and through

     and through.

up.

             down.

through.

up and down

     and through

          and through

     up and down

and through

     and through

          up and down

     and through

and through

     up and down

          and through

     and through.

down.

              up.

   through.

up and down

     and through

          and through

     up and down

and through

     and through

          up and down

     and through

and through

     up and down

          and through

     and through.

through.

down.

up.

again.