Millikan as an example

from Wikipedia

People seem to have these odd ideas that scientists are inhuman automatons who collect data, analyze all of it and then publish. They bring no real emotion to the mix. So when lab notebooks or emails reveal that human beings are involved, then some some people just freak.

So, read about Robert Millikan, who discovered the charge of an electron. Anyone who just read his lab notebooks or took quotes from his papers, without context, would call him a fraud. And people have. In books.

But as can be seen from David Goodstein’s defense (As an undergraduate at CalTech in the mid 70s, I heard David discuss this in a lecture and saw the copies of the lab notebooks. It was one of the pivotal seminars of my life), in context, not only is Millikan most like not guilty of any scientific malfeasance but his data were correct.

The supposed fraud comes mainly from this quoted sentence.

It is to be remarked, too, that this is not a selected group of drops, but represents all the drops experimented upon during 60 consecutive days, during which time the apparatus was taken down several times and set up anew.

He showed data in the paper for 58 drops during those 60 days but even the most generous examination of his notebooks reveal that he collected full data on 75 drops. He lied! He cherry picked data.

Of course, if one included all 75 drops, it has little effect on his results. So why did he commit fraud by ‘cherry-picking’ and then lying about it? It looks like he did neither.

First, there appear to be valid reasons for discarding some of the 75 drops. A drop that was too large or too small would be susceptible to other forces than he was examining.

Second, Goodstein makes the point that in the paper, when Millikan makes this statement, he is not referring to all the oil drops he examined in the lab. In the sentence, ‘all’ refers to the 58 drops he mentioned in a previous sentence, not to all the oil drops he might have observed.

The previous sentence:

It will be seen from Figs. 2 and 3 that there is but one drop in the 58 whose departure from the line amounts to as much as 0.5 percent.

The two sentences together from the original paper:

It will be seen from Figs. 2 and 3 that there is but one drop in the 58 whose departure from the line amounts to as much as 0.5 percent. It is to be remarked, too, that this is not a selected group of drops, but represents all the drops experimented upon during 60 consecutive days, during which time the apparatus was taken down several times and set up anew.

Furthermore, the ‘not a selected group’ was being used to determine another number, the Stokes radius (that is what figures 2 and 3 demonstrate), not the charge of an electron. He is trying to say that all of the oil drops that were used to determine the charge of the electron were also used to determine the Stokes radius. He did not cherry pick oil drop data in order to determine the Stokes radius. All the data he used in the paper to determine the charge were also used to determine the Stokes radius.

In context, it appears to be at worst an inelegant sentence. What looked bad in isolation turned out to be fine in context.

That is why context matters. No matter what some denialists say.

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