望梅止渴

wàngméizhǐkě
  1. lit. to quench one's thirst by thinking of plums (idiom)
  2. fig. to console oneself with illusions

CEDICT

to console oneself with illusions

Wiktionary

曹操率兵行军至途中，士兵乾渴难耐，曹操就骗士兵前有梅林，梅子又酸又甜，诱使士兵流出口水以解渴的故事。典出南朝宋．刘义庆《世说新语．假谲》。后比喻用空想来安慰自己。《警世通言．卷三四．王娇鸾百年长恨》：「鸾拆书看了，虽然不曾定个来期，也当画饼充飢，望梅止渴。」《初刻拍桉惊奇．卷一五》：「却那裡得这银子来！只好望梅止渴，画饼充飢。」也作「说梅止渴」、「望梅消渴」。

重編國語辭典

以空想来安慰自己

維基詞典

Entry Composition

=1 望 wàng
  1. full moon
  2. to hope
  3. to expect
  4. to visit
  5. to gaze (into the distance)
  6. to look towards
  7. towards
=1 望 wàng
  1. 15th day of month (lunar calendar)
  2. old variant of 望 wàng
=2 梅 méi
  1. plum
  2. plum flower
  3. Japanese apricot (Prunus mume)
=2 梅 méi variant of 梅 méi
=2 梅 méi old variant of 梅 méi
3 止渴 zhǐkě to quench one's thirst