Red pill and blue pill
The red pill and its opposite, the blue pill, are a popular cultural meme, a metaphor representing the choice between:

Knowledge, freedom, uncertainty and the brutal truths of reality (red pill)
Security, happiness, beauty, and the blissful ignorance of illusion (blue pill)The terms, popularized in science fiction culture, are derived from the 1999 film The Matrix. In the film, the main character Neo is offered the choice between a red pill and a blue pill by rebel leader Morpheus. The red pill represented an uncertain future—it would free him from the enslaving control of the machine-generated dream world and allow him to escape into the real world, but living the "truth of reality" is harsher and more difficult. On the other hand, the blue pill represented a beautiful prison—it would lead him back to ignorance, living in confined comfort without want or fear within simulated reality of the Matrix.