This objectivist would intervene. I've done it before, and would do it again.

My logic:
I am a semi skilled martial artist, pretty tough and pretty strong, therefore the risk to me is modest
Yes, there is risk to me, BUT
my action would provide confidence and incentive to others (present or learning of it) to also stand up for themselves/others
This supports my objective for the world of people to be self policing in such situations
The benefit far outweighs the risk.
Logically consistent.

The world, especially the US, needs to have many indigenous white blood cells among the population, not just knowledge of a 30 minute response to 911. This reduces fear and provides freedom!

There are many kinds of strength.

I am 5'7"...and I look like the archetypal, invisible, 'little brown woman'. You would not look twice at me if you passed me in the street - I could be anybody.

I have also done martial arts for >50 years. I would have been in that fight in an instant. I would have done my best to tear the knifeman's arm off, stick his own knife in his own eye, break his head, or perform some other type of socially-needed remediation for his personality.

I have pointed up a lot of responses on this thread. Bravo to the folks who would have acted! For those of you who said that you would have regarded it as philosophically correct not to have acted in defense of the victim, please be aware that if that is the type of society you laud and would construct from your philosophy: I will not be any part of it. That is not a world in which I would live.

My (late) mother, at 80 years of age and in ill health, would have tottered up to that fight and beat the attacker to death with a loaf of French bread. My father would have crawled off his death bed to tackle the knifeman around the ankles.

There are many kinds of strength.

Jan

Others addressed this well, so I'll just raise a couple of points.

1. Re United 93, the passengers had time to establish enough rapport to collaborate on a response. These people did not.

I would have looked around for eye contact with other ablebodied men to make a silent pact to attack. I have some police background, but I'm over 70 with significant strength limitations like torn rotator cuffs. The last time I intervened in a public physical situation I completely tore my left subscap. That required two surgeries to rebuild my left rotator cuff. I realize I can no longer act like a young, strong cop. And that leads to...

2. What if the average person were armed and trained?. That would change the context in this example and on Flight UA 93.

Im a rickety old guy, but I wouldn't be able to restrain myself. I might try shaming the crowd into action first by shouting something like "Are we going to let this punk get away with this? There are more of us than him!" Sometimes, the smallest incentive will get people to move. However, if this is an example of the new America, of "Millenials," I feel sorry for this country. It's lost its heart and maybe deserves its current fate.

I am a large but old man and much more stupid than brave, but I am sure I would have tried o stop the killing regardless.

I would intervene. As was said in the article, after the murder the thug robbed the other passengers. Something that surprises me not at all.

I refuse to be a passive victim. I am not altruistic, and consider it one of the greatest evils. I value my own life far more than some random thug. The odds of my being on the train empty handed are non-existent, and there is always something at hand. Improvised weapons may not be pretty, but they can be effective, and I don't fancy going against a knife with empty hands. If nothing else, a belt can be a bit of an equalizer.

I put it that the "heroic nature described as "selfless" was indeed NOT selfless in any way shape or form.

"This is essentially the opposite of the spirit of United Flight 93—the heroic selflessness that prompted a group of courageous passengers on 9/11 to attack their hijackers, .."

Under similar circumstances, my own self interest would dictate that attack is the best form of action to survive. while I may not succeed, and others might live, the point is for my OWN sake, I would attack knowing the certainty of not attacking is death.

This in a city that makes it almost impossible to carry a concealed weapon.

The author never faced the wrong end of a knife in a situation like this.

Helping someone in such distress is a secondary reason why I pack a pocket pistol is so I do not have to stand by and watch something like that.
Getting old with health issues, I'm not not fighting or grappling with any assailant even for my primary reason of self-preservation.
I'll just shoot the SOB.
Old Bama boy is also staying out of sorry places like Washington D.C. and birth state Massachusetts

I disagree with the author in the due unto others bit, and they weren't being selfish in the sense that Rand means it. Not being there, and only reading the article, I would have stepped in also. It was apparently a small knife, probably about the same size that I always carry, and there were enough people to overpower him. How many women had purses that could be swung hard, even if all it did was distract him from the attack and make him run? What if a few of the men yelled and took aggressive steps toward him? He likely would have stopped before he completed the kill. The fact that they all just stood there allowed evil to prevail.

In the case of the 911 crash, people were defend-
ing their country, and unwilling to live as slaves.
But I still find the behavior in the other incident
somewhat bizarre, as there were plenty of people
who could have ganged up together on the thug and wrested the knife from him, without very
much risk to themselves.

The author is either naïve or stupid. This incident is certainly not the same as on the 911 flight. In the latter case, everyone knew they were going to die without action. On the subway, everyone knew that they might die if they intervened. In both cases, people acted to save themselves because the risk was determined to be too great if they did the opposite.

You'd have to hold me back. He who attacks one of my fellow citizens without provocation, attacks me in the same action. I wouldn't vouch for that knife-wielder surviving the encounter.

I'm happy with the other responses so far. I believe it is in our rational self-interest to defend the right to life for all individuals, even when it isn't our own. And it's up to our own initiative, leadership, and creativity to do it in a way that doesn't threaten our own lives or values. This is a sad case when one person with initiative, courage, and leadership would have used strength in numbers to save a life from an immoral attack.

An interesting question for an Objectivist. I think from both a gut reaction and an Objectivist position, I'd have to try to stop the attack and I'd be yelling at others to help as well. Thuggery should never be rewarded with cowardice.

But I've been there, done that, and got the coffee cup. Most Objectivist have not been tested in such a manner. For that matter, not that many men in general have experienced this type of event. But I've also seen a lot of women step into such events as well without fear, and often times to shame the men there that haven't interfered. Though a brouhaha between two men on the other hand is not to be interfered with.

An objectivist would have acted to stop the murder because to do so would be to serve his values. A truly selfish person could not have stood by and watched that happen.

That story is a testimonial for the therapeutic effect of a concealed carry permit.

I imagine these DC metro type trains no longer have the cord that you can pull to stop the train?

This is primarily another story of the right to self defense having been taken away. Concealed carry, even a BIGGER knife - "Now, That's a Knife!" I think if I were a DC resident (forbid!), I would routinely carry a taser, a blackjack, ANYTHING to take control of a situation. That is what an objectivist would do.

While I certainly do not view ethics as a matter of survival-at-any-price, I would probably avoid getting myself stabbed by a man probably stronger and more battle-tested than myself, and I wouldn't feel guilt either. We don't have a duty to help strangers when our own lives would be put in danger -- that truly would be an ethic of self-sacrifice. What we have is a prudent judgment that we must make under the circumstances. Perhaps brave knights are to be praised for their courage, but there is no need for guilt over what is essentially not a duty.

I'll agree that if I could intervene without risking my life and health, then certainly I should. If I were to hear a rape taking place outside my apartment, I should at least call the police.

I recommend reading Ayn Rand's essay "The Ethics of Emergencies", plus David Kelley's book Unrugged Individualism, to get some depth on this issue.

I used to ride the commuter train to work. I decided that, because I would react in a way that would put myself at risk, I should stop riding the train. I've been driving in for about 8 years now.

It is not rational to put one's own life at risk to help a complete stranger generally speaking. There are circumstances where it would be though - principally where some deeper value is at stake than the proximate risk to one's life. In the situation described I don't see that this is the case. Now if it was a violent attack by government goons or if one's own life was in danger anyway then it might be rational to intervene directly.

How about three or four fellow passengers come at this idiot from 4 sides and confuse him. Just watch animal planet video to see how effective this is !

I would have assessed just what I could to to stop the killing without being seriously hurt, and enlisted the help of anyone else to accomplish this. Objects like handbags, coats, and such can be used as foils

Well I am stupid and I am also 6'4 and 220 lbs. For some idiotic reason when confronted with a situation like this I have a bad habit of jumping in and trying to stop the violence. I know I shouldn't but I always have.