Historical clue formulations

• Within the realm of reason — 2026-04-10
• Not ridiculous, as an argument — 2023-01-25
• Sound — 2022-05-06
• Not ridiculous, as an argument — 2019-08-25
• Sound — 2009-06-19
• Like a solid argument — 2009-05-27
• Well-founded — 2007-10-18
• Not easily debunked — 2005-08-28
• Not bad, as an argument — 2004-06-03
• Like a sound argument — 2003-07-13
• Like good arguments — 2001-12-07
• Like a good debater's arguments — 2000-11-02
• Like a well-grounded argument — 2000-04-23
• Easily defended — 1999-07-19
• Having some merit — 1999-02-11
• Solidly based — 1995-12-24