「杯子是半空還是半滿?」(英語:Is the glass half empty or half full?)是一句英語熟语,用於表達悲观主义者及樂觀主義者即使面對同一件事,亦會有不同看法——根據傳統觀點,乐观主义者會看到「杯子是半滿」,悲观主义者則會看到「杯子是半空」。部分人會以這一問題測試別人的世界觀[1][2][3][4]。
^Stephanie Stokes Oliver. Seven Soulful Secrets for Finding Your Purpose and Minding Your Mission. Crown Publishing Group. 2001-11-27: 106– [2013-08-07]. ISBN 978-0-385-48767-2. (原始内容存档于2021-08-03). I love that proverbial question, “Do you see the glass as half empty or half full?” It's like the litmus test for how you see the world. Optimists have a tendency to hope for the best. That doesn't mean they hope for the best sometimes. It means that ...