The quote "He who lives in a glass house should not try to kill two birds with one stone" suggests that those who are vulnerable or exposed should be cautious in their actions. It highlights the idea that taking risks or making aggressive moves can backfire, especially for those without solid defenses. This wisdom encourages individuals to be mindful of their circumstances before making bold decisions.

This saying from Vladimir Nabokov's book "Pnin" serves as a reflection on personal vulnerability and the complexities of decision-making. It implies that attempting to achieve multiple goals simultaneously can lead to negative consequences, particularly for those in precarious positions. Therefore, it is important to approach challenges wisely and thoughtfully.