Historical clue formulations

• Sharp mind, so to speak — 2021-04-16
• *Sharp mind, figuratively — 2014-12-15
• Symbol for a sharp mind — 2014-10-05
• Metaphor for a sharp mind — 2013-08-27
• *Metaphor for a sharp mind — 2013-02-14
• Comparison for some minds — 2000-12-30