From The History of Printing in America, by Isaiah Thomas (1810)
It was at first the determination of Thomas that his paper should be free to both parties which then agitated the country, and, impartially, lay before the public their respective communications; but he soon found that this ground could not be maintained. The dispute between Britain and her American colonies became more and more serious, and deeply interested every class of men in the community. The parties in the dispute took the names of Whigs and Tories; the tories were the warm supporters of the measures of the British cabinet, and the whigs the animated advocates for American liberty. The tories soon discontinued their subscriptions for the Spy; and the publisher was convinced that to produce an abiding and salutary effect his paper must have a fixed character. He was in principle attached to the party which opposed the measures of the British ministry; and he therefore announced that the Spy would be devoted to the support of the whig interest….
The printer of the Massachusetts Spy, or Boston Journal, was obliged to leave Boston, as has been mentioned, on account of the commencement of hostilities between the colonies and the parent Country. He settled in this place, and on the 3d of May, 1775, recommenced the publication of that paper, which he continued until the British troops evacuated Boston; when he leased it for one year to William Stearns and Daniel Bigelow . . . At the end of that term, the proprietor returned to Worcester, and resumed its publication, with a new motto—"Unanimity at Home, and Bravery and Perseverance in the Field, will secure the Independence of America." . . .
At the conclusion of the war the Spy was enlarged, and each page contained five volumes. It was printed from new types; and the motto was changed to '"Noscere res humanas est Hominis. Knowledge of the world is necessary for every man."