New American Standard Bible (©1995)
and I saw every work of God, I concluded that man cannot discover the work which has been done under the sun. Even though man should seek laboriously, he will not discover; and though the wise man should say, "I know," he cannot discover.

King James Bible
Then I beheld all the work of God, that a man cannot find out the work that is done under the sun: because though a man labour to seek it out, yet he shall not find it; yea farther; though a wise man think to know it, yet shall he not be able to find it.

Darby Bible Translation
then I saw that all is the work of God, and that man cannot find out the work that is done under the sun: because however man may labour to seek it out, yet doth he not find it; and even, if a wise man think to know it, he shall not be able to find it out.

English Revised Version
then I beheld all the work of God, that man cannot find out the work that is done under the sun: because however much a man labour to seek it out, yet he shall not find it; yea moreover, though a wise man think to know it, yet shall he not be able to find it.

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