Okay i was trying to get my head around this; i guess it could be done with a plugin..

Values:
Einsten = catID5 German = catID30 Scientist=catid45

Step 1:

List All categories

Step 2:

Choose one category to associate with others. catid5 per say.

Step 3:

Connect that catid5 with the other two catid30 and catid45

Step 4: save this relation to a table in the db.

Step 5: On each category click check if there are related categories and if there are select them too.

i will try to do sth around this, but i definitely need help, esp. with the plugin part. so again; any pointers will really help

Are you sure you'll actually save time doing this? It seems easier to check 2 extra boxes :-/

well, yeah, the idea seems like a pretty hard task, at least with my capabilities..But it is not just for me, i want users to contribute quotes to my quote db, and i dont want to make it hard for them, i mean i want to make it as easy as possible for them

You could cut out the whole js "tick/untick" stuff by interpreting category foo as ++ associated categories before you save/update the item ( BeforeItemUpdate/Create() or summat ).

That way they just need to tick "Einstein" and you interpret on the server ... gotta love degradation eh? ;)

¥