A decision may have any number of solutions. But a voting with only two options has the two options as its solution. This solutions forms the solution space of the voting. Affirmative and Negative . These two solutions has a equal probability of occurring. So my resolve is that my vote will fluctuate from affirmative to negative with each voting.
As long you are considering both the solutions, you chose the overall solution space. So, when you are having a probability of 1 in your hand your debate question becomes void since you took the overall solution space. Come on I think you know SET and Probability well.