-(* Unfortunately this is not enough to fully instantiate the intermediate state.
-All goals still depend from an unknown bank B. Calling automation in this situation
-does not help since it refuses to close subgoals instantiating other - still
-open - goals. A way to proceed is to focus on the fourth "bank" subgoal,
-instantiating it with the appropriate value, in this case east; then we close
-focusing, and call automation. To focus on subgoal i, instead of typing "|" several
-times we can just write "i:" as described by the following command. *)
-
- [4: @\ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,1,0)"\ 6east\ 5/a\ 6\ 5span style="text-decoration: underline;"\ 6\ 5/span\ 6] /2/
-
-(* An alternative, simpler way is to instantiate each move with the destination
-bank. Let us complete the proof adopting this style. *)
-
-@(\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,2,0)"\ 6more\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter1/move.con(0,1,0)"\ 6move_goat\ 5/a\ 6 \ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,2,0)"\ 6west\ 5/a\ 6 … )) /2/
-@(\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,2,0)"\ 6more\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter1/move.con(0,3,0)"\ 6move_cabbage\ 5/a\ 6 ?? \ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,1,0)"\ 6east\ 5/a\ 6 … )) /2/
-@(\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,2,0)"\ 6more\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter1/move.con(0,4,0)"\ 6move_boat\ 5/a\ 6 ??? \ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,2,0)"\ 6west\ 5/a\ 6 …)) /2/
-@\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,1,0)"\ 6one\ 5/a\ 6 /2/
-qed.
\ No newline at end of file
+(* The dots stand here for an arbitrary number of implicit arguments, to be
+guessed by the system.
+Unfortunately, the previous move is not enough to fully instantiate the new
+intermediate state: a bank B remains unknown. Automation cannot help here,
+since all goals depend from this bank and automation refuses to close some
+subgoals instantiating other subgoals remaining open (the instantiation could
+be arbitrary). The simplest way to proceed is to focus on the bank, that is
+the fourth subgoal, and explicitly instatiate it. Instead of repeatedly using "|",
+we can perform focusing by typing "4:" as described by the following command. *)
+
+[4: @\ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,1,0)"\ 6east\ 5/a\ 6] /\ 5span class="autotactic"\ 62\ 5span class="autotrace"\ 6 trace \ 5a href="cic:/matita/tutorial/chapter1/safe_state.con(0,1,0)"\ 6with_boat\ 5/a\ 6, \ 5a href="cic:/matita/tutorial/chapter1/opp.con(0,1,0)"\ 6east_west\ 5/a\ 6\ 5/span\ 6\ 5/span\ 6/
+
+(* Alternatively, we can directly instantiate the bank into the move. Let
+us complete the proof in this, very readable way. *)
+
+@(\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,2,0)"\ 6more\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter1/move.con(0,1,0)"\ 6move_goat\ 5/a\ 6 \ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,2,0)"\ 6west\ 5/a\ 6 … )) /\ 5span class="autotactic"\ 62\ 5span class="autotrace"\ 6 trace \ 5a href="cic:/matita/tutorial/chapter1/safe_state.con(0,1,0)"\ 6with_boat\ 5/a\ 6, \ 5a href="cic:/matita/tutorial/chapter1/opp.con(0,2,0)"\ 6west_east\ 5/a\ 6\ 5/span\ 6\ 5/span\ 6/
+@(\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,2,0)"\ 6more\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter1/move.con(0,3,0)"\ 6move_cabbage\ 5/a\ 6 ?? \ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,1,0)"\ 6east\ 5/a\ 6 … )) /\ 5span class="autotactic"\ 62\ 5span class="autotrace"\ 6 trace \ 5a href="cic:/matita/tutorial/chapter1/safe_state.con(0,2,0)"\ 6opposite_side\ 5/a\ 6, \ 5a href="cic:/matita/tutorial/chapter1/opp.con(0,1,0)"\ 6east_west\ 5/a\ 6, \ 5a href="cic:/matita/tutorial/chapter1/opp.con(0,2,0)"\ 6west_east\ 5/a\ 6\ 5/span\ 6\ 5/span\ 6/
+@(\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,2,0)"\ 6more\ 5/a\ 6 … (\ 5a href="cic:/matita/tutorial/chapter1/move.con(0,4,0)"\ 6move_boat\ 5/a\ 6 ??? \ 5a href="cic:/matita/tutorial/chapter1/bank.con(0,2,0)"\ 6west\ 5/a\ 6 … )) /\ 5span class="autotactic"\ 62\ 5span class="autotrace"\ 6 trace \ 5a href="cic:/matita/tutorial/chapter1/safe_state.con(0,1,0)"\ 6with_boat\ 5/a\ 6, \ 5a href="cic:/matita/tutorial/chapter1/opp.con(0,2,0)"\ 6west_east\ 5/a\ 6\ 5/span\ 6\ 5/span\ 6/
+@\ 5a href="cic:/matita/tutorial/chapter1/reachable.con(0,1,0)"\ 6one\ 5/a\ 6 /\ 5span class="autotactic"\ 62\ 5span class="autotrace"\ 6 trace \ 5a href="cic:/matita/tutorial/chapter1/move.con(0,1,0)"\ 6move_goat\ 5/a\ 6, \ 5a href="cic:/matita/tutorial/chapter1/opp.con(0,1,0)"\ 6east_west\ 5/a\ 6\ 5/span\ 6\ 5/span\ 6/ qed.
\ No newline at end of file