JESS: inferred to asserted

hi guys and girls,

i am using protege 3.4.4 with jesstab for my master-thesis and i am very new
with protege and jess.
what i want to do is this:

i want to create a rule that searches all the instances of a class and its
subclasses and than printout something or maybe change a slot.

the problem that i am having is that i dont have any access to all the
knowledge of protege because of the inferred and asserted knowledge or so i
thing at least.
i mean i can see in protege all the instances but i cannot access them
within my rule.

the code is something like this:

(clear)
(reset)
(mapclass ...)

(defrule Whatever "shows something."
(declare (salience 0) (no-loop TRUE))
?x <- (object (is-a classname)
)
(printout t "something " crlf)

)
 (run)


the classname has other subclasses for example

class: human
    subclass: man
    subclass: woman
    subclass: child

is there a way to convert inferrred instances to asserted?
or any other way that can halp me with my project?

thx for your time.