New Mexico's State motto, Crescit Eundo, meaning It grows as it goes, is found in Lucretius' De Rerum Natura, Book VI, Line 341. The New Mexico state motto was first used in 1882, when acting Territorial Secretary, William G. Ritch, added the Latin phrase Crescit Eundo to an early 1860's version of the territorial seal.
In 1887, Ritch's version of the seal, including the words 'Crescit Eundo,' was adopted by the legislature as part of the official New Mexico Territory seal and coat of arms.
Crescit eundo. Translated from Latin, it means "It grows as it goes" and has been criticized for appearing strange or even nonsensical at first hearing. However, the intended effect is more clear if one considers it within the context of the epic poem De Rerum Natura (On the Nature of Things) by first-century B.C. Latin poet Lucretius. Here, it refers to a thunderbolt increasing in strength as it moves across the sky, referenced by the selectors of the motto as a symbol of dynamic progress.
The motto was first used in 1882, when acting Territorial Secretary William G. Ritch added the Latin phrase "Crescit eundo" to an early 1860s version of the territorial seal. In 1887, Ritch's version of the seal, including the words "Crescit eundo," was adopted by the legislature as part of the official New Mexico Territory seal and coat of arms. Later when New Mexico became a state in 1912, the Legislature appointed a commission to settle on a design for an official "state" seal. The seal recommended by the commission and adopted by the Legislature was nearly identical to the territorial seal and included the words Crescit Eundo.
The law designating the official New Mexico state motto is found in the New Mexico Statutes Annotated
This statute describes the New Mexico seal. The motto is specified within this description.
CHAPTER 12 - Miscellaneous Public Affairs Matters.
ARTICLE 3 - State Seal, Song and Symbols.
12-3-1. [State seal; design.]
The coat of arms of the state shall be the Mexican eagle grasping a serpent in its beak, the cactus in its talons, shielded by the American eagle with
outspread wings, and grasping arrows in its talons; the date 1912 under the eagles and, on a scroll, the motto: "Crescit Eundo." The
great seal of the state shall be a disc bearing the coat of arms and having around the edge the words "Great Seal of the State of New Mexico."