That means,"Out of many, one."
Notice the similarity in the following two quotations:
"Be strictly honorable in every act, and be not ashamed to do right."
"We must use time creatively and forever realize that the time is always ripe to do right."
Both quotations are from letters. The first one is from a correspondence Robert E. Lee wrote to his son. The second is from Martin Luther King, Jr's. "Letter From a Birmingham Jail." (For Lee: Wyatt-Brown, Honor and Violence in the Old South, 1986, p. 57; for King: Washington, ed. I Have a Dream: Writings and Speeches that Changed the World, 1986, p. 92.)
On the surface Lee and King couldn't be more different. One man lived in the nineteenth century, the other in the twentieth. One man was white, one was black. Both were respected leaders for opposite causes; Lee led military forces fighting to preserve chattel slavery while King struggled to eliminate the last remaining vestiges of bondage. These days diversity is hailed as a value, and if you had Lee and King in your workplace you couldn't get more diversity in two men, although granted you wouldn't want any contrasting viewpoints in your operation on the issue of slavery--everybody has to say "no" to it.
In spite of their dissimilarities, in thhe quotations presented here both Lee and King emphasized the importance of doing right. I'm sure Lee and King, regardless of their differences, would probably agree on about ninety percent of what constitutes doing right. Treat people with respect, treasure your loved ones, help a friend in need. In what may be a divisive election year, those are values everyone should agree on. Listen to the other person's viewpoint and try to consider his or her point of view; don't automatically dismiss opinions contrary to yours as unsound or absurd.
When we value other people we live up to the motto on our coins. Out of many, one. E pluribus unum.