Orange County

 "The most effective way to do it is to do it." - Amelia Earhart

 signs placed on the 5, 405 and 91 freeways in Orange County, California.

 "I am driven by two philosophies: know more about the world today than I did yesterday and, along the way, lessen the suffering of others. You'd be surprised at how far that gets you." - Neil deGrasse Tyson

 "As far as we can discern, the sole purpose of human existence is to kindle a light in the darkness of mere being." - Carl Jung

 "I’m not convinced that faith can move mountains, but I’ve seen what it can do to skyscrapers." - William Gascoyne

Total - 6,828

Oakland/Richmond

"You may be able to fool the voters, but not the atmosphere." - Donella Meadows

 Signs placed over and alongside Interstate 580 in Oakland and Richmond, California.

 "If the freedom of speech is taken away then dumb and silent we may be led, like sheep to the slaughter." - George Washington

 "Injustice is relatively easy to bear. What stings is justice." - H.L. Mencken

 "One of the things you do when you make a piece of art is you try to make the world you'd rather be in." - Brian Eno

 "Rules are made for people who can't make up their own." - Chuck Yeager

Total - 6,818

Sonoma County

 "Together we shall save our planet, or together we shall perish in its flames." - John F. Kennedy

 Signs placed alongside US 101 in Sonoma County, California.

 "Begin at once to live, and count each separate day as a separate life." - Seneca

 "The trouble with words is you never know whose mouths they've been in."  - Dennis Potter

 “The future depends entirely on what each of us does every day.” - Gloria Steinem

 "I'm going to get an MRI to find out if I have claustrophobia." - Steven Wright

Total - 6,810

Marin County

 "Life must be lived as play." - Plato

 Signs placed over and alongside Highway 101 in Marin County.

 "The most useful thing about a principle is that it can always be sacrificed to expediency." - W. Somerset Maugham

 "Look deep into nature and then you will understand everything better." - Albert Einstein

 "There was never a good war or a bad peace." - Benjamin Franklin

 "We all shine on, like the moon, and the stars, and the sun." - John Lennon

 "They who dream by day are cognizant of many things which escape those who dream only by night." - Edgar Allen Poe

 "The higher the building the lower the morals." - Noel Coward 

TOTAL - 6,803

Berkeley

 "Make good use of the present." - Horace

 Signs placed on Interstates 80 and 580 in Berkeley, California.

 "Though familiarity may not breed contempt, it takes off the edge of admiration." - William Hazlitt

 "The supreme art of war is to subdue the enemy without fighting." - Sun Tzu

 "Be ashamed to die until you have won some victory for humanity." - Horace Mann

 "There is nothing impossible to him who will try." - Alexander the Great

Total - 6,794

Los Angeles

 "I always wondered why somebody doesn't do something about that. Then I realized I was somebody." - Lily Tomlin

 Signs placed on freeways in Los Angeles and the San Fernando Valley.

 "All great truths begin as blasphemies." - George Bernard Shaw

 "We all believe in the regulations, but you have to know how to interpret them." - Mario Vargas Llosa 

 "Worried about dry skin? Concerned about lines and wrinkles? Then visit a burn ward and get some perspective." - Shaun Micallef

 “The good thing about science is that it's true whether or not you believe in it.” ― Neil deGrasse Tyson

 "If the terrorists hated freedom, the Netherlands would be dust." - David Cross

TOTAL - 6,786