intelligence/age

My 18 month old kitten has been pulling open cabinet doors and the door to my sunroom since I first got him at 8 weeks old. He learned it pretty quickly from watching my other cat pull open the bathroom door, who was 18 months old at the time. I think my kitten might have a knack for opening things though, because his technique now includes stretching up to the doorknob, putting one paw on each side and turning it to unlatch the door before he tries pulling or pushing.

Some cats just don't want to pull open doors. In my experience, it's the most curious ones, the ones who can't stand to have any door in the house closed because they want to know what's on the other side, who bother to try and figure out doors. Some cats are too lazy and couldn't care less as long as there is a warm spot available.

EDIT: Haha, just as I finished typing this, I heard the doors to the cabinet under my bathroom sink rattle. When I went to check it out, I found my kitten playing around inside the cabinet, with the door closed behind him (for anyone reading this, don't worry, I don't keep anything toxic down there).

My Paige, King Arther and even Phoebe on occassion love showing me all their tricks and how smart they are.  Paige taught King Arthur to open cabinet doors when he was about 4 months old. He takes it a step further now, after watching me, he closes them, too!!  It is so funny!!  I am in awe of how smart he is!!  He knows how to use the remote to turn the tv up and down and change the channels.  How to turn it off and on.  He also does tricks I taught him... Which I also taught the girls, he's just too big now. 

When Phoebe was about a year old, I taught her how to jump onto my shoulders from the refridgerator (a good 2 ft drop).  Impressive for a Persian... Paige learned it at 3 months.  I taught King Arthur around the same age.  Paige takes it a step further and will jump up onto my shoulders.  They all do lots of other stuff too... I could go on and on.

It depends on the activeness of the cat in my opinion.  I don't consider Piper or Morgan La Fay any less intelligent because they don't do "tricks".. They are intelligent in their own ways and too dignified to lower themselves to performing tricks for treats! HA!