Ecc 3:11 -- "eternity" or "world" in heart?

[nwink]

What causes the difference in translation of the word "eternity" or "world" in Ecc 3:11?

KJV: "He hath made every thing beautiful in his time: also he hath set the world in their heart, so that no man can find out the work that God maketh from the beginning to the end. "

ESV: "He has made everything beautiful in its time. Also, he has put eternity into man’s heart, yet so that he cannot find out what God has done from the beginning to the end."

 

[rbcbob]

The Hebrew word occurs in over 400 verses in the Old Testament. It generally means "of long duration" and occurs in Eccl 3:14 where both the KJV and the ESV translate it "forever".