Albert Barnes Commentary Ecclesiastes 7:25

"I turned about, and my heart [was set] to know and to search out, and to seek wisdom and the reason [of things], and to know that wickedness is folly, and that foolishness is madness." — Ecclesiastes 7:25 (ASV)

Reason - The same word is translated “account” (Ecclesiastes 7:27), “invention” (Ecclesiastes 7:29), and “device” (Ecclesiastes 9:10): it is derived from a root signifying “to count.”