Index: /issm/trunk/src/m/classes/verbose.m
===================================================================
--- /issm/trunk/src/m/classes/verbose.m	(revision 7871)
+++ /issm/trunk/src/m/classes/verbose.m	(revision 7872)
@@ -52,5 +52,9 @@
 					fieldvalue=options.list{i,2};
 					if ismember(fieldname,properties(verbose)),
-						verbose.(fieldname)=fieldvalue;
+						if islogical(fieldvalue) | isnumeric(fieldvalue),
+							verbose.(fieldname)=logical(fieldvalue);
+						else
+							error('verbose supported field values are logicals only (true or false)');
+						end
 					else
 						disp(['''' fieldname ''' is not a property of verbose verbose']);