Lucky Knowledge
It can be tempting to assume that the explanation for why a subject lacks knowledge in reverse lottery stories must have something to do with its being a matter of luck that she has a true belief about the winning ticket, but this is a temptation to be resisted. What matters is whether her true belief is surrounded by adequate information, not whether she has been lucky.
Here is another lottery-like story to help illustrate this point. Imagine one hundred people in a room, each of whom knows that he or she is about to take part in an experiment. Each will be put into a machine that will make one of the group clairvoyant while providing the other ninety-nine with impressions about the future that are as vivid and convincing as those had by the genuine clairvoyant, only misleading.1
After the machine does its work, each subject believes that he or she is the one who has been made clairvoyant, and each also believes that all the other subjects are pseudo-clairvoyant. The lucky subject is S. Like the other ninety-nine, she believes she is clairvoyant, but unlike the others, her belief is true. Still, it might seem that she is not in a position to know she is clairvoyant, but if not, what is the important gap in her information?
Like all stories, this one is selectively incomplete, and there are different ways of filling it in. The story is not explicit, for example, about what information S has about the machine and the experiment. If we fill in the story to make clear that after the machine has turned her into a clairvoyant, she lacks information about how the machine produces clairvoyance in the lucky subject, how it produces pseudo-clairvoyant appearances in the unlucky subjects, and how it is that she became the lucky subject, all these gaps are available to explain why she doesn’t have enough information to know she is the clairvoyant one.
On the other hand, suppose we fill in the story so that in the process of becoming clairvoyant, she also acquires detailed and accurate information about all these matters. She has full information about the machine, the experiment, and the conditions that led to her becoming the lucky subject. She thus begins to resemble Sally who has beliefs as comprehensive and accurate as it is possible for a human to have, and it accordingly becomes more plausible to say she knows.
To the degree there is an impression that luck is incompatible with knowledge, it arises because in everyday situations when one luckily acquires a true belief, one commonly does lack knowledge. Recall the original barn case in which George has a true belief that he is looking at a barn, but it is just happenstance that he has stopped his car in front of the few remaining real barns in the region instead of a barn facsimile. As the story has been told, it is a matter of luck that his belief is true, but his being lucky is also correlated with his not being aware that there are nearby barn facades. He is both lucky and ignorant. Blind lucky, as it were.
By contrast, once it is stipulated that S has complete and detailed information about how the clairvoyance machine produces clairvoyance and pseudo-clairvoyance and how it is that she came to be the clairvoyant one, there is still luck involved in her having knowledge, but not blind luck. Like Sally she has all the relevant information.
In a global sense, knowledge always requires good fortune. Brain-in-a-vat stories illustrate that things beyond one’s control and awareness can conspire to prevent one from having true beliefs despite one’s best efforts. One can be ideally careful and thorough and yet still be deceived. This point is perfectly general. One needs the world to cooperate in order to have knowledge.
The assumption that luck is incompatible with knowledge arises out of the local workings of luck, such as are operative in the barn case. In these cases, however, there is corresponding local ignorance. Remove the ignorance, that is, remove the blindness from the luck, and knowledge becomes possible.2