At the rate things are going someone is going to have to compile a volume under the title of “The Quotable John Roberts.” The chief justice of the United States may lack some of the biting humor and rhetorical flair of the The Great Scalia, but what the new chief lacks in bombast he’s been making up for — just in the last few days alone — with a pithy good sense.

Earlier this week, overturning McCain-Feingold’s pre-election ad ban, Justice Roberts gave us the dictum that “where the First Amendment is implicated, the tie goes to the speaker, not the censor.” And now he’s given us a new one, in his majority opinion released yesterday in two cases — Parents Involved in Community Schools v. Seattle School District and Meredith v. Jefferson County Board of Education — that will prevent public school districts from assigning primary and secondary school children on the basis of race.

“The way to stop discrimination on the basis of race,” Justice Roberts wrote, striking down race-based student-assignment systems in Seattle, Wash., and Louisville, Ky., “is to stop discriminating on the basis of race.”

At issue in the two cases were systems designed to ensure that the racial makeups at individual kindergarten, primary schools, and high schools roughly matched the racial makeups of the school district as a whole. The goal of these systems, ostensibly, is decidedly noble, to prevent “resegregation” of our public schools along racial lines. Yet the result has been the continuing use of race as a criterion in assigning students to one school over another. One plaintiff was a white mother in Louisville whose son was denied a transfer to attend kindergarten in a school that needed to keep its black population at the district’s required minimum of 15%.

Supporters of these schemes claim it is all for the good of the students: Children who go to integrated schools are more racially tolerant than other children; black children who go to racially balanced schools perform better academically than other black children. Forget that the social science on these matters is far from settled, Justice Thomas notes, in a concurring opinion with some much-needed perspective. The racists of another era used just such social-science-based arguments to justify continued segregation: “Can we really be sure that the racial theories that motivated Dred Scott and Plessy are a relic of the past or that future theories will be nothing but beneficent and progressive?”

Those looking to improve the lot of all disadvantaged public-school students — black, white, Hispanic, and all other races, religions, and creeds — can look to what will now come to be seen as a more important Supreme Court decision: the 2002 case of Zelman v. Simmons-Harris, where the High Court determined that school vouchers, even for religious schools, were permissible under the Establishment Clause of the First Amendment. It is choice and free-market competition that will give these students the key to a better education and a brighter future.