Well, I think the thrust of the quote had more to do with being confident in your own projects. But I'll try to do an answer to your point because I think it's important to recognise the limitations of domain specialists - some of whom just aren't very good at their jobs.

If you're not on your team of expert surgeons, you're gonna be screwed if they're not actually as expert as you might think they were. There's a bit in What Do You Care What Other People Think? Where Feynman is talking about his first wife's hospitalisation - and how he had done some reading around the area and come up with the idea that it might be TB - and didn't push for the idea because he thought that the doctors knew what they were doing.

Then, sometime later, the bump began to change. It got bigger—or maybe it was smaller—and she got a fever. The fever got worse, so the family doctor decided Arlene should go to the hospital. She was told she had typhoid fever. Right away, as I still do today, I looked up the disease in medical books and read all about it. When I went to see Arlene in the hospital, she was in quarantine—we had to put on special gowns when we entered her room, and so on. The doctor was there, so I asked him how the Wydell test came out—it was an absolute test for typhoid fever that involved checking for bacteria in the feces. He said, "It was negative." "What? How can that be!" I said. "Why all these gowns, when you can't even find the bacteria in an experiment? Maybe she doesn't have typhoid fever!" The result of that was that the doctor talked to Arlene's parents, who told me not to interfere. "After all, he's the doctor. You're only her fiancé." I've found out since that such people don't know what they're doing, and get insulted when you make some suggestion or criticism. I realize that now, but I wish I had been much stronger then and told her parents that the doctor was an idiot—which he was—and didn't know what he was doing. But as it was, her parents were in charge of it.

Anyway, after a little while, Arlene got better, apparently: the swelling went down and the fever went away. But after some weeks the swelling started again, and this time she went to another doctor. This guy feels under her armpits and in her groin, and so on, and notices there's swelling in those places, too. He says the problem is in her lymphatic glands, but he doesn't yet know what the specific disease is. He will consult with other doctors. As soon as I hear about it I go down to the library at Princeton and look up lymphatic diseases, and find "Swelling of the Lymphatic Glands. (1) Tuberculosis of the lymphatic glands. This is very easy to diagnose . . ."—so I figure this isn't what Arlene has, because the doctors are having trouble trying to figure it out.

[Feynman moves onto less likely possibilities]

One of the diseases I told Arlene about was Hodgkin's disease. When she next saw her doctor, she asked him about it: "Could it be Hodgkin's disease?" He said, "Well, yes, that's a possibility." When she went to the county hospital, the doctor wrote the following diagnosis: "Hodgkin's disease—?" So I realized that the doctor didn't know any more than I did about this problem. The county hospital gave Arlene all sorts of tests and X-ray treatments for this "Hodgkin's disease—?" and there were special meetings to discuss this peculiar case. I remember waiting for her outside, in the hall. When the meeting was over, the nurse wheeled her out in a wheelchair. All of a sudden a little guy comes running out of the meeting room and catches up with us. "Tell me," he says, out of breath, "do you spit up blood? Have you ever coughed up blood?" The nurse says, "Go away! Go away! What kind of thing is that to ask of a patient!"—and brushes him away. Then she turned to us and said, "That man is a doctor from the neighborhood who comes to the meetings and is always making trouble. That's not the kind of thing to ask of a patient!" I didn't catch on. The doctor was checking a certain possibility, and if I had been smart, I would have asked him what it was. Finally, after a lot of discussion, a doctor at the hospital tells me they figure the most likely possibility is Hodgkin's disease. He says, "There will be some periods of improvement, and some periods in the hospital. It will be on and off, getting gradually worse. There's no way to reverse it entirely. It's fatal after a few years."

[Gets convinced to lie to her that it's Hodgkins - lie falls through]

For some months now Arlene's doctors had wanted to take a biopsy of the swelling on her neck, but her parents didn't want it done—they didn't want to "bother the poor sick girl." But with new resolve, I kept working on them, explaining that it's important to get as much information as possible. With Arlene's help, I finally convinced her parents. A few days later, Arlene telephones me and says, "They got a report from the biopsy." "Yeah? Is it good or bad?" "I don't know. Come over and let's talk about it." When I got to her house, she showed me the report. It said, "Biopsy shows tuberculosis of the lymphatic gland." That really got me. I mean, that was the first goddamn thing on the list! I passed it by, because the book said it was easy to diagnose, and because the doctors were having so much trouble trying to figure out what it was. I assumed they had checked the obvious case. And it was the obvious case: the man who had come running out of the meeting room asking "Do you spit up blood?" had the right idea. He knew what it probably was!

I felt like a jerk, because I had passed over the obvious possibility by using circumstantial evidence—which isn't any good—and by assuming the doctors were more intelligent than they were. Otherwise, I would have suggested it right off, and perhaps the doctor would have diagnosed Arlene's disease way back then as "tuberculosis of the lymphatic gland—?" I was a dope. I've learned, since then.

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Point being, disinvolving yourself from decisions is not a no-risk choice, and specialists aren't necessarily wise just because they've sat through the classes and crammed some sort of knowledge into their heads to get a degree. Assigning trust is a difficult subject.

There's a book called The Speed of Trust - and that's pretty much what you give up in being involved in complex decisions where you're not a specialist and where the specialists are actually really good at their jobs - a bit of speed.