כִּ֛י בְּרֹ֥ב חָכְמָ֖ה רָב־כָּ֑עַס וְיוֹסִ֥יף דַּ֖עַת יוֹסִ֥יף מַכְאֽוֹב׃
For in much wisdom is much vexation; And he that increaseth knowledge increaseth sorrow.
Read kabbalistic (mystical) interpretation of Ecclesiastes 1:18: and classical mystical sources.