It Isn’t the Mountain Ahead That Wears You Out; It Is the Grain of Sand in Your Shoe

Muhammad Ali? Robert W. Service? Anonymous? Dear Quote Investigator: The following quotation about perseverance is attributed to the famed boxer Muhammad Ali: It isn’t the mountains ahead to climb that wear you out; it’s the pebble in your shoe. While I was researching this phrase I came across another version that was attributed to the …