On 2010-03-04, at 10:16 PM, Igor Stasenko wrote:

> Agreed. But then expect an Object class to have thousands of isXXXX
> methods, since we having way many things which we can imagine and may
> want to model them. Then the Object class will become a flat space of
> system-wide methods. Is this what can be called good OO design which
> using polymorphic dispatch?

You exaggerate. In my image, Object has 51 methods that begin with 'is'. It's hardly a flat space of system-wide methods. 

In general, I agree that Object has too many methods. But I think we should reduce that number by *increasing* the modularity of the system, rather than decreasing it.

Colin