Suppose Smith and Jones apply for the same job. And suppose Smith is justified in believing both that (1) Jones will get the job, and (2) Jones has 10 coins in his pocket. Smith would then also be justified in believing that (3) the person who gets the job will have 10 coins in his pocket. In fact, Smith (not Jones) gets the job and, as it happens, he has 10 coins in his pocket. (3) turns out to be a justified true belief, but it doesn’t seem that Smith knows (3). Of course, Smith should believe (3), but not for the reasons that he does. He has a true belief, but not knowledge.

The legacy of the Gettier counter-examples was a powerful one: a justified true belief isn’t knowledge when the justification for the true belief isn’t the cause of why the agent holds the belief.