When Chief Justice John Roberts Jr. congratulated President Obama after he completed his oath of office on Monday, Americans heard the cordial, affirming voice that regularly fills the courtroom of the Supreme Court. But the chief justice’s graciousness did not mean he was endorsing the president or his views.

As the president’s Inaugural Addressmade plain and as important rulings of the Roberts court show, the Obama and Roberts visions of America are very different. No disagreement is more fundamental than that about the connection between justice and prosperity.

To Mr. Obama, prosperity enables justice and vice versa. Persuasively, he said in his address, “Together, we discovered that a free market only thrives when there are rules to ensure competition and fair play.” He also said, “We are true to our creed when a little girl born into the bleakest poverty knows that she has the same chance to succeed as anybody else.” And commitments to justice, likeMedicare, Medicaid and Social Security, he said, “do not make us a nation of takers; they free us to take the risks that make this country great.”

The Roberts court, on the other hand, with the chief justice in the majority, has regularly ruled as if justice and prosperity are unrelated or even antithetical — by protecting large corporations from class-action lawsuits; by making it much harder for private lawsuits to succeed against mutual fund malefactors, even when they have admitted to lying and cheating; or by allowing corporations and unions to spend unlimited amounts of money on political campaigns and advance their narrow interests by exerting influence unjustly over government.

When the chief justice cast his critical vote to uphold the Affordable Care Act last June, he made clear that he did not favor the law, which is the most important commitment to justice and prosperity so far of the Obama administration. He wrote tartly, “It is not our job to protect the people from the consequences of their political choices.”

The connection between justice and prosperity is clear and strong. “Economic growth,” the scholar Benjamin Friedman documented, “more often than not fosters greater opportunity, tolerance of diversity, social mobility, commitment to fairness and dedication to democracy.” And justice of all kinds, especially social justice, is an essential means of achieving prosperity, as economic progress in the South demonstrated after the civil rights laws brought racial progress.

The Supreme Court will hear arguments in the coming months about the continuing need for a critical section of the Voting Rights Act that prevents racial discrimination and about the basic rights of gay Americans. Those cases are unquestionably about justice and fundamental issues of fairness. But their outcomes will inevitably affect prosperity as well, because they deal with issues of participation in American society and, as a result, in the American economy.

The cameras lingered on President Obama after the inaugural ceremony just before he entered the Capitol, as he turned back toward the Mall and took in the crowd of a million or so of the American people whose general welfare he again swore to promote. When Chief Justice Roberts administered the oath, he had a similar chance to be reminded of the multitudes to whom the Supreme Court pledges “Equal Justice Under Law” — and to be reminded of the strong link between justice and prosperity.