Justice Stevens was willing to learn on the job.
What is written above is the NYT headline of Greenhouse's column on John Paul Stevens. And what does the NYT's mean when it says Stevens was willing to "learn on the job"?
At one time, Stevens had the opinion that racial preferences violated the equal protection guarantees of the 14th Amendment. Later on, Stevens changed his mind and decided that the government could discriminate by granting preferences, set asides & quotas based on race and/or ethnicity.
And when you do that, the NYT's calls it "learning".