Is it simply comparing apples to oranges?

In a discussion on gun control, my opponent put forth the argument (and attached articles) that more people are killed with knives in London than by guns in New York and a report of multiple deaths caused by a mass-murderer in China using a knife. His logic was that if we're going to place restrictions on firearms, then we should also put them on knives because knives are deadly too. I know that the logic of the comparison is faulty but I didn't know if it had an official name.

Just a quick response. This is a clear Slippery Slope argument.

Nearly 1.25 million people die in road crashes each year, on average 3,287 deaths a day. An additional 20-50 million are injured or disabled. More than half of all road traffic deaths occur among young adults ages 15-44.

Road Safety Facts — Association for Safe International Road Travel

Should we outlaw cars?

Yes, clearly a slippery slope.

Also a dubious analogy. Firearms have no purpose other than to kill or injure. But a knife can be used to cut tomatoes and carrots, to carve your sweetheart's name in a tree stump, or to cut a parachute cord if you get stuck in a tree, etc. The comparison doesn't really work b/c the two cases are quite different.

Apples to oranges seems reasonable as well. Anyway, your buddy's thinking seems muddled and defensive.

I agree with both Michael and Dr. Harpine. Perhaps I can just add some strategy to make your response more convincing. The first fallacy is the weak (dubious) analogy . Pointing out the weak analogy is rarely effective without explaining why it is weak. Listing the reasons is a good start (e.g., how guns are used primarily for killing, etc.) but still unlikely to convince the person who made the weak analogy. I would start with the slippery slope fallacy here:

His logic was that if we're going to place restrictions on firearms, then we should also put them on knives because knives are deadly too.

This argument is the result of black and white and even simplistic thinking where the person is unable or unwilling to see nuance. The implied "rule" here is that anything that can be deadly should have the same restrictions. This can easily be shown to be absurd by using extremes. Should a nuclear weapon have the same restrictions as a golf club? Once the person agrees that this would be absurd, ask why. Let the person come to the understanding themselves. Once you can both agree that there are should be clear restriction differences between the two extremes, then it logically follows that things that can be deadly should not all have the same restrictions. Once you reach this point, you can attempt to demonstrate how guns are more different than knives than similar.

I think there's several problems with your opponent's argument. I'm new here, and at the moment I don't have the time to study and learn the jargon, but I'll give it a try.

First, your opponent is executing what I would call a Lateral Arabesque: If you can't successfully argue a subject, change the subject and argue that. Even if your opponent's statistics are correct -- a very dubious assertion -- the issue is gun control, not knife control. To argue that people are killed with knives in London constitutes a valid reason people in the U.S. should be allowed to indiscriminately carry guns with no social control is quite a sideways dance. You could simply ask your opponent to stay on the subject.

Second, based on my experience, anyone who argues against gun control is arguing in favor of gun use. Point that out. But be alert. Your opponent may pull a gun.

Third, as the good doctor has pointed out, You could execute your own Lateral Arabesque by suggesting that hammers can also be lethal but it's a lot easier to pull a trigger on impulse (or even accident) than to blugeon on impulse (or accident).

Fourth, like using a mixed metaphore, your opponent is employing mixed metaphoric logic. Ask your opponent how many toddlers he thinks accidentally knife their siblings? You may not like that approach, but you could point out that you are only employing the same sort of (non)logic that he is.

Fifth, and this is only a shot in the dark, is the time duration of fatal stabbings in London the same as the duration of fatal shootings in New York? I'll bet they're not. Perhaps one is for last year while the other is for last month.