Let's say you and I are out to lunch and a very thin woman walks by. I make a disgusted face and say to you, "Ugh, she is just CANCEROUS." I think you would be a little taken aback at my harshness. Let's say a young man walks by the table and trips on something on the floor and I yell, "Nice walking, Palsy!" You'd probably be looking for a place to hide. But let's say you are telling a funny story about something really stupid you did on a date and I go, "OMG, you are such a RETARD!" Most people would probably just laugh harder. This is what people who are diagnosed with mental retardation (and their families) face on a daily basis in our society. While it would be considered very insensitive to make fun of someone with cancer or ALS or MS, it is considered perfectly acceptable to use the medical diagnosis of mental retardation as a synonym for doing something stupid.
The word "Retard" (and permutations such as "Fucktard" and "Libtard") are prevalent in our society. There are Facebook groups called "Retarded Mom", "Americans Against Libtards" and "Fucktards Unite". When special needs advocates have petitioned Facebook to remove those groups as hate speech, the response from the Facebook Quality Control Department is, "Your complaint has been reviewed and no violation has been found." As in: IT'S PERFECTLY ACCEPTABLE to compare someone with political viewpoints that differ from your own with someone who has a medical condition resulting in a lowered IQ and developmental delays. GO RIGHT AHEAD! Nothing wrong with posting pictures of people with average intelligence doing stupid things with the heading "Retards." I have seen everyone from nurses to lawyers to special education teachers using these words.
I have actually seen people use the argument that people with mental retardation don't know enough to be insulted, so who are they hurting? This point of view is so ignorant, I don't even know where to start. Clearly, there are millions of people who are classified as mentally retarded (or "intellectually delayed", as is the preferred term these days. These are people whose IQ falls below 70) who are perfectly capable of carrying on normal conversations, caring for themselves and holding jobs. These people, such as actress Lauren Potter of Glee, who was born with Down Syndrome, will tell you flat out that using these words HURTS THEIR FEELINGS. See for yourself:
Here is the bottom line: If you use the "N" word, you cannot expect black people to want to have anything to do with you. If you use the "F" word, you cannot expect gay people to want to have anything to do with you. And if you use the "R" word, in any of its iterations, do not expect my child or myself to want to have anything to do with you. You have been put on notice.