Bridge
Bridge
[A youthful Cueball talking to an unseen parent.] Parent: No, you can't go. Cueball: But all my friends— Parent: If all your friends jumped off a bridge, would you jump too? Cueball: Oh, jeez. Probably.
Parent: What!? Why!? Cueball: Because all my friends did. Cueball: Think about it — which scenario is more likely:
Cueball: Every single person I know, many of them levelheaded and afraid of heights, abruptly went crazy at exactly the same time... Cueball: ...or the bridge is on fire?
Parent: ...I, uh...hmm. Cueball: Imagine reading this on CNN: " Many fled their vehicles and jumped from the bridge. Those who stayed behind... " Cueball: Is something good about to happen to those people? Parent: Maybe they'll find cookies? Cueball: OK, you stay. I'm jumping.

"If all your friends jumped off a bridge, would you jump too?" This is a common question, used to challenge a decision based on the bandwagon effect . It challenges someone to consider whether something is really a good idea, even if everyone else does it (in this case, friends). The sentence is, upon closer analysis, a straw man attack that over-extrapolates the bandwagon effect.
Cueball responds by assuming that if all of his friends jumped off a bridge, there must have been some extreme circumstance that made it logical to do so; for example, that the bridge is on fire. This points out a logical fallacy with the question: if they really are jumping off a bridge, they're probably motivated by something serious as opposed to an idiotic risk. So the humor of this comic is in all the different ways the question can be turned on its head, and made to mean something the unseen speaker probably never intended.
The title text suggests that, even if there is nothing wrong with the bridge, the person asking the question is not acting right. The proper reaction would be concern about the mental (or physical, they could be injured) state of the people jumping off for no valid reason, and not just brushing them off as unworthy of attention. This is so especially when these people are described as "all my friends", so they have presumably always behaved correctly until they decided to jump off the bridge.
[A youthful Cueball talking to an unseen parent.] Parent: No, you can't go. Cueball: But all my friends— Parent: If all your friends jumped off a bridge, would you jump too? Cueball: Oh, jeez. Probably.
Parent: What!? Why!? Cueball: Because all my friends did. Cueball: Think about it — which scenario is more likely:
Cueball: Every single person I know, many of them levelheaded and afraid of heights, abruptly went crazy at exactly the same time... Cueball: ...or the bridge is on fire?
Parent: ...I, uh...hmm. Cueball: Imagine reading this on CNN: " Many fled their vehicles and jumped from the bridge. Those who stayed behind... " Cueball: Is something good about to happen to those people? Parent: Maybe they'll find cookies? Cueball: OK, you stay. I'm jumping.
