Before Ronald Reagan traveled the 16 blocks to the White House after his first inaugural address, the White House curator had, at the new president’s instruction, hung in the Cabinet room a portrait of Calvin Coolidge. The Great Communicator knew that “Silent Cal” could use words powerfully — 15 of them made him a national figure — because he was economical in their use, as in all things.

Were Barack Obama, America’s most loquacious president (699 first-term teleprompter speeches), capable of learning from someone with whom he disagrees, he would profit from Amity Shlaes’ new biography of Coolidge, who she calls “our great refrainer” with an “aptitude for brevity,” as when he said, “Inflation is repudiation.”

She says that under his “minimalist” presidency, he “made a virtue of inaction.” As he said, “It is much more important to kill bad bills than to pass good ones.” During the 67 months of his presidency, the national debt, the national government, the federal budget, unemployment (3.6 percent) and even consumer prices shrank. The GDP expanded 13.4 percent.

In 1898, at 26, he won his first of 10 public offices, a seat on the City Council of Northampton, Mass. Like Reagan, Coolidge benefited from being underestimated. The letter of reference he carried to Boston when elected to Massachusetts’ General Assembly said, “Like the singed cat, he is better than he looks.” Tougher, too. During the chaos of the 1919 Boston police strike, Gov. Coolidge electrified the nation with these 15 words: “There is no right to strike against the public safety by anybody, anywhere, any time.”

Nine months later, Republican leaders in the famous “smoke-filled room” in Chicago’s Blackstone Hotel decided to nominate for president Ohio Sen. Warren Harding, whose dreadful rhetoric (“not nostrums, but normalcy … ”) drove H.L. Mencken to rhapsodies of disgust. The convention produced a rhetorically balanced ticket by stampeding for Coolidge as vice president.

When Harding died in August 1923, the new president — assisted by a splendidly named former congressman, C. Bascom Slemp — continued Harding’s program of cutting taxes, tariffs and expenditures.

“I am for economy. After that I am for more economy,” said the 30th president, whose administration’s pencil policy was to issue one at a time to each bureaucrat, who if he or she did not entirely use it up had to return the stub.

Coolidge and Treasury Secretary Andrew Mellon advocated “scientific taxation,” an early iteration of the supply-side economics theory that often lowering rates will stimulate the economy so that the government’s revenue loss will be much less than the taxpayers’ gain. Soon Coolidge was alarmed that economic growth was producing excessive revenues that might make government larger.

He met his wife, the vivacious Grace, after hearing her laughter when she saw through a window that he was shaving while wearing a hat. Shlaes’ biography would be even more engaging had she included this anecdote:

When President and Mrs. Coolidge were being given simultaneous but separate tours of a chicken farm, Grace asked her guide whether the rooster copulated more than once a day. “Dozens of times,” she was told. “Tell that to the president,” she said. When told, Coolidge asked, “Same hen every time?” When the guide said, “A different one each time,” the president said: “Tell that to Mrs. Coolidge.”

In 1924, after the lingering illness and death of his 16-year-old son from blood poisoning, Coolidge demonstrated — if only our confessional culture could comprehend this — the eloquence of reticence: “When he was suffering he begged me to help him. I could not.”

Coolidge, says Shlaes, thought his office “really was one of ‘president,’ literally one who presided.” And “the best monument to his kind of presidency was no monument at all.” This absence, however, is a kind of admonitory presence for him who said, “It is a great advantage to a president, and a major source of safety to the country, for him to know he is not a great man.”