Elon Musk expects his employees to be so committed to their work that he once scolded a Tesla coworker for missing a company event to witness the birth of his child.

That's according to Ashlee Vance's forthcoming book, Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future, which quotes the (anonymous) employee in question, who recalls that Musk emailed the following to him:

"That is no excuse. I am extremely disappointed. You need to figure out where your priorities are. We’re changing the world and changing history, and you either commit or you don’t."

At a time when more and more of corporate America seems focused on financial engineering and flushing cash out to shareholders, there is something genuinely admirable about Musk's determination to pursue game-changing innovations. On the other hand, taken to this extreme it becomes a real sickness.

As a new father, I find it rather astounding that Musk managed to write that without getting punched in the face. Even in pure cutthroat business terms, it's difficult to imagine that Tesla is going to be able to attract and retain engineering talent over the long run if this is genuinely the CEO's attitude toward his staff.

You can see more in Matt McFarland's roundup of astounding quotes from the book.

Update: On Twitter Tuesday morning, Elon Musk took issue with this characterization of events:

Of 22 Quotes from http://t.co/VA2KQ03NNR, 2 need correcting: 1. I strongly support pregnancy leave 2. I've never called myself a samurai — Elon Musk (@elonmusk) May 12, 2015

And: