The essence of human existence is that it is singular and irreplaceable, meaning we experience life only once. This uniqueness implies that we cannot revisit our choices to judge whether they were right or wrong. Each decision we make is final, and this permanence adds weight to our choices, as we navigate life without the luxury of comparison.

This notion emphasizes the complexity of decision-making in our lives. Since every choice is made without the opportunity for a second trial, we are left with the uncertainty of whether we could have pursued different paths. The concept raises profound questions about fate, freedom, and the nature of existence itself.