An Etymological Dictionary of the German Language/Annotated/denken

by Friedrich Kluge

denken, verb, ‘to think, call to mind, conceive, believe,’ from Middle High German dęnken, Old High German dęnchen, ‘to think, bear in mind, devise, excogitate’; corresponds to Gothic þagkjan (þankjan), ‘to consider, ponder, reflect,’ Anglo-Saxon þęncan. English to think, is an intermediate form between Anglo-Saxon þęncan, ‘to think,’ and þyncan, ‘to seem.’ Denken is in form a factitive of dünken, which was originally a strong verb, meaning ‘to seem’; ‘to make a thing seem’ is ‘to consider, ponder.’ See dünken.