On the issue of the quote, it has often been attributed to Sagan or Rees, but examples can be found in the late 1800s. I have run across it many times in the work of other writers.
An early use was in the question of whether an ice sheet could have existed, given the lack of a glacial moraine in the area. But moraines sometimes are eroded away, so an absence is not evidence for the absence of an ice sheet many thousands of years ago.
If this question were asked in modern times, we could survey the area for evidence of isostatic depression and rebound. Finding none, we could conclude that no thick ice sheet had been there for tens of thousands of years, as the evidence for isostasy does not vanish in that time. Absence of evidence in this case would be evidence of absence.
English usage has changed a bit since 1880. Today we might say "Absence of evidence is not necessarily evidence of absence.". A bit weasel-worded but accurate.
In the 1880s I think that they would have felt that "not" was not equivalent to "never" and understood that sometimes the saying did not apply.
| Date | Sujet | # | | Auteur |
| 1 Apr 26 |  Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 346 | | ShyDavid |
| 1 Apr 26 |  Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 2 | | RonO |
| 2 Apr 26 |    Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | ShyDavid |
| 1 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 343 | | MarkE |
| 2 Apr 26 |  Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 61 | | RonO |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 58 | | MarkE |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | RonO |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 5 | | ShyDavid |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | Kerr-Mudd, John |
| 4 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 3 | | MarkE |
| 4 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 2 | | RonO |
| 4 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | ShyDavid |
| 4 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 51 | | Martin Harran |
| 4 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 29 | | Ernest Major |
| 5 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 28 | | Martin Harran |
| 6 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 22 | | John Harshman |
| 6 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 21 | | Martin Harran |
| 6 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 20 | | John Harshman |
| 6 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 3 | | Ernest Major |
| 6 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | John Harshman |
| 7 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Martin Harran |
| 6 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Ernest Major |
| 7 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 15 | | Martin Harran |
| 8 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 14 | | John Harshman |
| 8 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 13 | | Martin Harran |
| 8 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 12 | | John Harshman |
| 9 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 11 | | Martin Harran |
| 9 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 10 | | John Harshman |
| 9 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | William Hyde |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 8 | | ShyDavid |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 7 | | John Harshman |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 4 | | ShyDavid |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | John Harshman |
| 13 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 2 | | John Harshman |
| 13 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | RonO |
| 13 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 2 | | Martin Harran |
| 13 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | John Harshman |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 5 | | WolfFan |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 3 | | ShyDavid |
| 10 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Kerr-Mudd, John |
| 12 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Mark Isaak |
| 13 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Martin Harran |
| 16 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 21 | | Kerr-Mudd, John |
| 16 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 20 | | sticks |
| 16 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | ShyDavid |
| 16 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Vincent Maycock |
| 17 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Kerr-Mudd, John |
| 18 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 15 | | Martin Harran |
| 18 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 14 | | sticks |
| 18 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | ShyDavid |
| 20 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 11 | | Mark Isaak |
| 20 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 10 | | sticks |
| 21 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 9 | | Mark Isaak |
| 21 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 8 | | sticks |
| 23 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 7 | | Mark Isaak |
| 23 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 6 | | sticks |
| 23 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Vincent Maycock |
| 25 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 4 | | Mark Isaak |
| 25 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 3 | | sticks |
| 26 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Vincent Maycock |
| 27 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Mark Isaak |
| 20 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Martin Harran |
| 18 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Mark Isaak |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 2 | | MarkE |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | RonO |
| 2 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 281 | | ShyDavid |
| 4 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 280 | | MarkE |
| 6 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 253 | | MarkE |
| 6 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 252 | | ShyDavid |
| 6 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 2 | | sticks |
| 7 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | ShyDavid |
| 6 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 249 | | MarkE |
| 7 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 248 | | MarkE |
| 7 Apr 26 | gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 247 | | Kerr-Mudd, John |
| 7 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 246 | | MarkE |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 244 | | RonO |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 242 | | MarkE |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 239 | | RonO |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 238 | | MarkE |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 237 | | RonO |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 236 | | MarkE |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 221 | | RonO |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 219 | | MarkE |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 218 | | RonO |
| 11 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 217 | | MarkE |
| 11 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 188 | | RonO |
| 11 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 187 | | MarkE |
| 12 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 186 | | RonO |
| 12 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 143 | | MarkE |
| 12 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 142 | | RonO |
| 13 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 141 | | MarkE |
| 13 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 140 | | RonO |
| 13 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 139 | | MarkE |
| 14 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 138 | | RonO |
| 14 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 2 | | MarkE |
| 14 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | RonO |
| 15 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 135 | | Martin Harran |
| 15 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 132 | | Kerr-Mudd, John |
| 15 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 131 | | Martin Harran |
| 15 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 1 | | Kerr-Mudd, John |
| 15 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 129 | | RonO |
| 15 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 2 | | MarkE |
| 13 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 42 | | Martin Harran |
| 15 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 28 | | sticks |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | ShyDavid |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 11 | | Kerr-Mudd, John |
| 10 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 3 | | ShyDavid |
| 9 Apr 26 | Re: The Debate Has Been Settled - Creationism Has Won | 2 | | Martin Harran |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | ShyDavid |
| 8 Apr 26 | Re: gods (was april fool: Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | ShyDavid |
| 6 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 25 | | Mark Isaak |
| 6 Apr 26 | Re: Effective Tomorrow, We Will Be Archiving the newsgroup. The Debate Has Been Settled — Creationism Has Won | 1 | | RonO |