What's the logical fallacy in this joke?

Factual Questions
1

Guy comes home from work, panting, trying to catch his breath, plops down at the kitchen table.
Wife says, “So why are you so exhausted?”
Guy says, “Honey, instead of taking the bus home from work today, I ran all the way behind it and saved $2.50!”
Wife says, “Schmuck! Why didn’t you run behind a taxi, and save $15?”

I like this joke and tell it all the time, to mixed results. The thing is I can never put my finger on where the logical hole is (to mix a metaphor). At the risk of killing a joke by analyzing it, could anyone break it down for me?

I strongly believe that this kind of (il)logic is constantly used by politicians, bad businessmen, and crafty accountants. To anyone helping out, if it suits them, I think it’s OK to use these professions’’ familiar propositions to demonstrate the logic of the thing, not as personally held political positions, etc.

2

Confusion of cause and effect?

The wife has failed to notice that it’s the choice of which vehicle to habitually ride to work, rather than the choice of which vehicle to run behind instead of riding, that determines how much money you save when you run instead of riding.

3

I’m not sure if I can point to a formal logical fallacy, but it revolves around the idea of “what is saving?” Just because you thought about spending money but didn’t doesn’t mean you actually saved anything.

People on a diet give themselves credit for passing up that big piece of chocolate cake, but your body doesn’t know about what you chose not to eat; it only knows what you eat.

If he usually takes the bus, but today ran and had $2.50 in pocket that he normally wouldn’t have had, then he indeed saved $2.50. But if he had run behind the taxi his pocket wouldn’t know the difference.

Related joke:
“Honey! I got a new dress for free today!”
“Free? Wow! How did you manage that?”
“Well, it was on sale for 50% off and I paid for it with the half I saved!”

This is similar to claims made by the current administration about how many jobs were “saved” by the stimulus.

4

He saved $2.50 if he usually takes the bus. If he usually takes the cab, then he saves $15 by running, and would have saved $12.50 if he had taken the bus. It doesn’t matter what vehicle he runs behind, just which one he usually takes.

And where in the world does a bus cost $2.50, but a cab costs $15? Everywhere I’ve seen, the buses cost less, the cabs cost more, or both.

5

The last thirteen words of this statement are befuddling. In at least three, maybe four ways. That’s a pretty high befuddlement::word count ratio. Here are a few befuddling things:[ol][li]Those are pretty common prices for those modes of transportation. If I want to get to campus (in Philadelphia), I can take public transportation for $2.15, or a cab for about $14. In Chicago, riding the bus and taking one transfer is $2.25, and there are plenty of destinations that’ll cost you $15 in a cab. So whence Chronos’ confusion?[]In the second sentence, he gives a series of three disjunctive possibilities. I.e. {A} or {B} or {A and B}. This disjunction implies that {neither A nor B} is impossible. However, the premises given are mutually dependent. Like {heads I win} or {tails you lose}. You can’t have one without the other. How then can the first two items on the list be disjunctive?[]How can you have the third item on the list, and still have it be disjunctive? Either heads I win, or tails you lose, or both?? Either I am shorter than my brother, or my brother is taller than I, or both?? How could it be anything but both?[*]It’s possible he means that buses cost less than $2.50 and cabs cost more than $15, which would make his statement a lot more sensible than my default interpretation (i.e. that buses cost less than cabs, or cabs cost more than buses). However, if this is what he meant, then how could he possibly say that a cab costs more than a given amount? A cab just costs the flag drop (usually a couple of bucks) plus mileage or time. You can have a five-dollar cab fare. And who wants to work such a distance from home that it costs more than $15 to get home in a cab?[/ol][/li]Not trying to be critical. Just thought y’all might get a chuckle out of my bemusement.

6

Yeah, that’s what I meant. Around here, a 15-mile cab ride would cost you about $20. Maybe the cabs around here are just a huge ripoff, but in most regards, cost of living here is low. The buses here, meanwhile, are free, but I recognize that that’s not typical.

7

In higher-density areas with more non-car-owners, there may be a higher percentage of shorter/cheaper cab rides. In my own city, I can easily spend $3 on a bus trip that would definitely cost me less than $15 in a cab. (I’d have to transfer from one bus to another to bring the fare up to $3, but it’s certainly a possible option.)

8

From “Burns and Allen”

George) Nice to see you made it on time this week.

Gracie) Thanks George, I was in the park and I ran all the way to the studio

George) That’s quite a way

Gracie) That’s why I ran. I wanted to get here before I got tired.

…And now back to your regularly scheduled thread :slight_smile:

9

Dear recent threaders (and you know who you are), from the OP:

Knock this off and get back to the OP, or may the curse of the OP be on your head.

I know I’ll regret providing this information, but to clear the deck, the bus rate $2.50 because in NYC its $2.15 and the exactitude is not the point (foolish me).

[FONT=Trebuchet MS]The [/FONT]taxi rate here is:
[FONT=Courier New]$2.50 upon entry[/FONT]; $0.40 for each additional unit The unit fare is:
one-fifth of a mile, when the taxicab is traveling at 6 miles an hour or more; or 60 seconds when not in motion or traveling at less than 12 miles per hour.
A mile in NYC is 20 blocks.

The only thing conceivably real-world about the savings of $15 is that a man can do it and it less than a trivial amount, a fact intuitively understood by the hearer of the joke (who lives in the city, etc.) and gives it enough verisimilitude for the surprise to be funny, thus making the whole anecdote a j. But you knew that.

BTW, you can ride miles and miles and back for the same $2.15, but usually a taxi is more expensive, even on the bus’s short hops through regular traffic. On the other hand, the taxi could be jammed in the same traffic as the bus, and you could hang around with it and get home with the same savings. There are zillions of other scenarios in which the cost/distance/human running ability is altered. The guy could be on crutches. There could be a gas main explosion. The kitchen table may have had exploding spikes on it. Sheesh.

Try to resist addressing that part of the joke as valid or not. That is not the OP’s point. The OP’s answer is not fully baked, as it were.

:mad: Get back to my joke already!! :mad: The Burns and Allen one is an excellent one, but whose logic is not exactly the same trick as mine, I think. The fallacy in the two of them is undoubtedly related, and it would be nice to see it taken apart. The Marx Brothers have a lot of these jokes, as does their admitted follower, Becket, in Godot.
*Yours truly, a reformed hijacker (it depends on whose ox is being gored, I now see),
*Leo Bloom

10

Perhaps it’s just a case of false comparison. The appropriate comparison is between spending money on bus fare or not spending it (which makes a difference of $2.5). The wife invokes a false comparison between the price of the bus fare and the price of the taxi fare, which is irrelevant to ‘money saved by not spending it on bus fare’.

11

I’m not sure if there is an accepted name for this fallacy but it has to do with an incorrect assumption of what the base case is. Related to this is a problem in assuming that the status quo is the base case. That is, in some cases, if you do nothing the current situation will change due to outside factors.

12

It reminds me of an old joke, possibly on The Flintstones?

Wife: I saved $50 on this dress I bought today.
Husband: Well, why didn’t you buy three more so we could save enough for this month’s mortgage payment?

13

Clearly this joke comes in various forms. And it is an essential part of real-world marketing, as I mentioned in the OP. When the sales tag says “marked down from $50,” it looks like a good deal. When it says “marked down from $100,” for the same product, more people will buy it, because it’s “a better deal.”

Sadly, my wife falls for this all the time–:(-- although usually I don’t mind because it gives her so much pleasure.*

*And of course I still love her to pieces!:D:D:D

14

You guys are all overanalyzing this. The joke is; how would the taxi driver know where the guy lives? Running behind a random taxi wouldn’t get you home at all, much less $15 to the good.