it is cruel if it is done as an adult, declawing, tail docking, ear cropping etc. do it when they are very young and its fine. my wifes cat still has his claws because he had them when we adopted him, he was 2-3 years old. they now do it with lasers and the recovery time is 75% faster, atleast according to my vet. but she said at his age he would be in a lot of pain and not forget about it. babies, wether cat, dog or human or other, are born with a lot more soft cartilage in their joints. as they age much of that cartilage becomes harder bone. as a 4 year old cat, Jack would havea lot of pain, or a lot more than a kitten would have.