Final answer:
The phrase alludes to the significant impact a single individual can make by speaking out, especially in contexts where most remain silent. The power of one voice can shape policy, affect change, and influence group narratives.
Step-by-step explanation:
The phrase 'When the whole world is silent, even one voice becomes powerful' suggests that in situations where there is a lack of communication or advocacy on a matter, the act of one person speaking out can be incredibly impactful. This echoes ideas presented by Dr. Martin Luther King Jr. who articulated the importance of speaking out against injustices. Similar to how great ideas enter gently into the world or how an individual's voice in a deliberative assembly can shape policy outcomes, the phrase emphasizes the significant effect one voice can have in shaping the narrative, inspiring change, or bringing attention to overlooked issues. The context in which a message is delivered can also greatly influence its reception and the power it holds, such as noted in the usage and evolution of political slogans.