112 
DR. SCHWARTZ: I am sorry, that is not a complete answer to your ques- 
tion, because the second problem is this. Even if you identified a sequence 
that leads to faults, if you then assume that you just take the probability — 
suppose you have good information on what the component probabilities are, 
which I claim you do not have, then there is still the problem that it is not 
necessarily the case that just by multiplying those probabilities together, a 
process that tends to make the number very small, because you are multiplying 
small numbers together, and you get even smaller, much smaller rapidly. That 
is not justified, unless you can show that there is good reason to believe 
that the various parts of that sequence are unconnected. 
Let me give you one example. For example you might say that the proba- 
bility of an organism infecting a person is certainly unconnected with the 
probability of its escape. But I point out that when the person is working 
on a new organism, a person is very likely to be very excited, very likely to 
be short on sleep and rest and so forth, and therefore there is a chance that 
there is a connection between the nature of the organism and the suscepti- 
bility of the experimenter, that they are not necessarily independent. 
MR. HELMS: Well, perhaps what I could ask here is that you could take 
a look at the things that are listed under dispersion of potential hazardous 
agents on page 99 and 100 — 
DR. SCHWARTZ: I need a copy. 
MR. HELMS: Not right this minute, but perhaps give us something in 
which you would explain how you would assess these probabilities. Would you 
say that these are events which do not have to occur in order for something 
untoward to occur? — and also give us some idea of how you would go about 
this . 
DR. FREDRICKSON: If we have time this evening, that would be possible. 
Mr. Hutt. 
MR. HUTT: As a follow-up to that, Dr. Schwartz, you say you criti- 
cized Dr. Holliday's paper. Have you published your criticism, and if so, 
could we have copies of it? 
DR. SCHWARTZ: I have a letter I wrote to the BBC on that. I guess 
we can get it copied. 
MR. HUTT: I am sure. 
DR. MC CARTHY : We will be glad to provide you with copies. 
MR. HUTT: Are you aware of any other published criticism of it, or 
unpublished criticism that would be available? 
DR. SCHWARTZ: No, I don't think so. 
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