On 11 November 2010 11:11, anais <amartinez(a)iti.upv.es&gt; wrote: I think that this paragraph (Expert 3.3.3.1.3. Update) contains several obsolete statements. <quote> The Rule Engine must be notified of modified facts, so that they can be reprocessed. <rem>OK</rem> Internally, modification is actually a retract followed by an insert; the Rule Engine removes the fact from the WorkingMemory and inserts it again. <rem>This isn't literally true. For instance, the fact handle isn't recreated, and this is where the automatic timestamp resides.</rem> You must use the update() method to notify the WorkingMemory of changed objects for those objects that are not able to notify the WorkingMemory themselves. Notice that update() always takes the modified object as a second parameter, which allows you to specify new instances for immutable objects. The update() method can only be used with objects that have shadow proxies turned on. <rem>A long time ago, perhaps.</rem> The update method is only available within Java code. <rem>Not true, it can be used in RHS code as well.</rem> On the right hand side of a rule, also the modify statement is supported, providing simplified calls to the object's setters. <rem>Usually preferred to setter calls followed by update().</rem> </quote> No. No. No need to do this, I'd say. -W