I hear it all the time. 'Revenge is not an emotion or instinct that animals can grasp'.
I say that's crap. There is nothing you can say to me that will convince me that my cat doesn't plot and get revenge.
I will say, however, that I roll my eyes anytime somebody tells me their dog takes revenge for things. Dogs are a creation of God. Cats are a creation of the devil.
Sylvester is a greedy creature. Not in the way of my Labrador. He's greedy, too. But in a different way. Sylvester believes he is entitled. To the following things:
The other recliner
All overstuffed arms of said furniture
Every rug in the kitchen
A personal wait staff
Bubbles baths of champagne
100% of my attention, even though there are 5 other beings in the house that require my attention
If Sylvester doesn't get these things, he makes me regret it.
Example; Last night, I was running low on cat food. So he got a smidgen less for dinner than normal so that I'd have enough for his breakfast and then I could grab a new bag today. Well apparently Syl counts his kibbles every meal, because as soon as he was finished, he whipped around, yowling and following me around for more. (After a normal meal, Syl generally sits down on a rug, licks his chops, cleans his paws, and uses his litter box).
This morning, I awake to an angry Red, who immediately insists that I look at his chair, and then look at the loaf of bread I bought over the weekend. I groggily glance at his recliner, which has some mysterious orange stuff spewed all over it. Then I make my way to the kitchen and discover that Syl has knawed through the bag and chewed the tops off of no less than 6 slices of bread.
I return to Red and tell him that it appears as though Kitteh got into the bread and then later realized he ate way too much, and being too lazy to get off his compfy perch at the top of Red's recliner, blew chunks all over the chair. And I wouldn't doubt for a minute that Syl then went on to snooze for a good 6+ hours, happy with life in general. But not yet satisfied that he'd gotten revenge.
No, the revenge part comes when he gets to watch me from his perch, on my hands and knees trying to clean up his mess with a rag. Before I've even touched my first cup of coffee! That, my friends, is the ultimate feline revenge.
Don't you dare try and tell me that cats don't understand what revenge is. They do, and they know how to carry it out with a scary kind of flawlessness.