This is a real travesty. While sexual harassment deserves suspension from future teaching, the existence of Lewin's (highly regarded and instructive) lectures in no wise endorses or encourages sexual harassment, and their loss is truly detrimental.
First, as others have pointed out, the linked statement suggests (without providing details) that MIT was concerned that Lewin would continue a pattern of using his connection with their online courses to harass students. Without being privy to their investigation we don't know what all led to that ongoing concern, but it's plausible to assume they have reasons.
Second, it may be that MIT's policy in these cases is to formally cut all ties with the harasser, or something to that effect. This might be the online equivalent of insisting that a disgraced emeritus professor give up their office on campus. There are clearly downsides to the community for such a policy, but there are indisputable benefits as well.
And finally, it strikes me that MIT has very little leverage to punish a retired professor who damages the university's reputation and community in this way. But this action of taking down a big part of his life's work is a way of hitting him right in his legacy. I know that were I in his shoes, I would be devastated by such a decision. I hope it has a strong deterrent effect on any other faculty who might be prone to similar abuses of their positions.
This is something I really didn't need to read on the internet today. Hitting a physicist right in his legacy. I'll just turn off my computer now, I'm seeing red, can't write a reasonable response to that.
Math and the other sciences don't suffer from this as much these days: folks drift away there, too, but the gender disparity isn't as great. Among the natural sciences, it's just physics that sticks out.[0] So yeah, right in his legacy. I'm actually pretty happy to see punishments with teeth for guys whose actions perpetuate the situation.
[0] To the extent that computer science is a math/science subject, it's worth noting that CS has plummeted down to near-physics levels of gender disparity in recent years. I think it's very likely that similar cultural issues are at work.
As you say, they wouldn't remove an author's books in this case. How are course notes and videos any different?
Poor decision, in my opinion.
> Following broad consultation among faculty, MIT is indefinitely removing Lewin’s online courses, in the interest of preventing any further inappropriate behavior.
It sounds like they're worried that just having courses up (even if not offered) might encourage future interaction between students using the material and the person listed as instructor (e.g. by email), which they don't want to provide as an avenue. They do have an archive of past courses [1], so one in-between option might've been to remove them from the current MITx site and stick them in the archive. But it's possible they were worried that would be insufficient. (It's also possible I don't understand how MITx courses are organized, and what the archive is for.)
Another interpretation is that other current or future faculty could get ideas about sexually harassing online students. "... preventing any further inappropriate behavior..." sounds like they're worried about other current or future faculty being pervs, and want to nuke him from orbit.
Walter Lewin's course took me from failing physics to loving the field so much that I switched my major from comp sci to physics.
I am disgusted that MIT chose to respond in this way. An institution of learning should know better than to do the digital equivalent of a book burning.