113 
MR. HUTT: Have you made an independent calculation that would be 
comparable to his that would show what your estimate of the risk would 
be? 
DR. SCHWARTZ: No, not on this basis. 
MR. HUTT: On any other basis? 
DR. SCHWARTZ: Yes, another basis is to assess what has been the suc- 
cess of recent technology. 
Now, I look at this as an outsider. I am strictly an outsider, and 
I say you look at all of the technologies that have been going on, let us 
say, since the time of the Second World War--all Second World War and post- 
Second World War technologies. The rate of serious problems has been great, 
roughly 30 percent. 
MR. HUTT: My question is, though, whatever the basis might be, have 
you projected from a mathematical model, or experience, a calculation of 
risk? 
DR. SCHWARTZ: I wouldn't call it a mathematical model, but we are 
dealing with a subjective probability here, and I think some people are 
beginning to work more on the problem of dealing with subjective prob- 
abilities, because you can't really test the whole system. 
MR. HUTT: Let me rephrase my question. Have you written down your 
theory or method of subjective probability in a form that would be useful 
to the Committee? 
DR. SCHWARTZ: Yes. I have another copy of a letter to another radio 
station, and I can give you a copy of that as well. 
DR. FREDRICKSON: Dr. Neel, a final question for Dr. Schwartz. 
DR. NEEL: I think the crux of the issue here is whether these prob- 
abilities are independent or not, or whether, to quote one of Murphy' s—or 
is it Parkinson's — laws, when things can go wrong, they generally will. 
It might be interesting for the record if the Committee would give us 
their thinking about a chain — a first error touches off a second error, 
which is basically what you are arguing, and that leads to a third error. 
In other words, the nonindependence of the probabilities that occur in 
Holliday's article. 
DR. FREDRICKSON: I think we would now like to turn to Mr. Thacher, 
who was scheduled to comment. Is he still here? I think you said you 
had a couple of brief comments to make. 
[ 317 ] 
