I’m reading this now, awake… unless I’m not awake. Lucid dreamers challenge the assumed, default state of "awake" with tests like looking in a mirror or at their hands. Once they understand they’re asleep, they can enjoy their unrestricted reality.

Many bits of knowledge in my mind hold such importance that they’re certainties: plans in motion, shared memories, self-narratives. It’s good to occasionally challenge these certainties so that I have a better understanding of myself and reality. The challenge ought to be earnest, without my thumb on the scale, in order to provide useful feedback.

How can I challenge a certainty?

• Take a cue from George Costanza and do the opposite action. Dress it up however I need to. Maybe I’m acting, maybe it’s a silly thing to tell a friend later. If it’s all mental, think the opposite thought: “I’m afraid” becomes “I’m not afraid.”
• Try many approaches. Brainstorm a list of every variable relevant to the certainty and tweak them individually.

Something that may have once been true may no longer be true, and the challenge will reveal this shift. Or it’s still true and the challenge will reinforce it. Either outcome is beneficial, so it’s worth an honest effort.