Big cat isn't as stupid as we sometimes think looking at the smaller examples, haha.
I'm going to take this for what it's worth.
A simple house cat is very intelligent, but people seem to think otherwise because they are so used to seeing dogs do tricks. Cats are capable of doing the exact thing if they are trained correctly. The only downside with cats is they would rather take a nap then do your tricks.
When my Willie was a kitten, I taught him a few things immediately. I made a sound by rubbing my fingers together, and gave him loving when he came to it out of curiosity. He recognizes this sound now and will come to me for potential loving. If he was acting up or jumping on tables etc. I snapped my fingers, grabbed him and bit into his neck hard enough so that he knew I meant business. Nowadays, a finger snap would make him bend his ears and run.
My old buddy Ume was the smartest cat I knew. He was very vocal. A meow for "good morning/feed me" when I woke up. A nervous "me me me me meow" for when I got angry. Grrrr for when the UPS guy approached the door. His death was hard on me, especially because he was so depressed at the end and refused any kind of loving - that was the hardest thing I had to go through yet.
My cat doesn't walk on tightropes or jump through hoops but I've seen it done. A guy in Key West does a street act using ally cats he befriends. These aren't the top of the breed cats. Key West is a small island so retarded inbreed cats are common - they have this stoner look to them like they're always out of it. But they seem to follow commands for a piece of tuna.