One of the responses to Pascal’s Wager is that it may be meaningless to assign a probability to a certain metaphysical proposition such as God’s existence.
In this post about the assignment of probability with respect to metaphysical realities, @Conifold comments,
The assignment is of course meaningless, along with "more", "less", "many other", etc., applied to something as vague as "metaphysical possibilities". See Bertrand paradox for a simple illustration of how probability values depend on arranging "possibilities" into a sample space. Even if one was willing to accept the "base assumption" of equiprobability it is impossible to make sense of what that means here.
Suppose that you are a person who thinks that it is meaningless to assign a probability to God’s existence or that you think the probability of God’s existence is unknown given the lack of experience with any supernatural entities.
Now, in the interpretation of subjective probability, which is often linked to Bayesian thinking, probability is defined as a degree of belief as such:
Your degree of belief in E is p iff p units of utility is the price at which you would buy or sell a bet that pays 1 unit of utility if E, 0 if not E
The neat thing about this definition is that it defines probability in a practical way, in the form of a bet.
Now imagine that this bet is somehow forced upon you, either by the government, or by punishment in such a way where you have no choice but to take this bet. Now, a person who is forced to take this bet where he can only pick between 0 and 1 units, must still take an action (or else, he may be murdered for example).
But if he does pick a number of units (think of this as real money), which he must, does this not mean that he undeniably has a credence in the proposition (which can be translated into a probability) even if he claims not to, making him inconsistent?
Note that if the terms of this bet still seem unrealistic, you can waive these concerns by not thinking of the bet too literally:
These problems stem largely from taking literally the notion of entering into a bet on E, with its corresponding payoffs. The problems may be avoided by identifying your degree of belief in a proposition with the betting price you regard as fair, whether or not you enter into such a bet; it corresponds to the betting odds that you believe confer no advantage or disadvantage to either side of the bet (Howson and Urbach 1993). At your fair price, you should be indifferent between taking either side.
Disclaimer: I am not myself a Bayesian and don’t know on which side of the fence I belong here yet (unless, of course, I was forced to bet on it ;))
P.S. to the current downvoters, explain the downvotes instead of being cowardly, especially since answers by prominent posters have already been given, giving at least some level of indication that they thought the question was worth responding to. This site unfortunately has a wonky history of downvoting/closing things without explanation which is sometimes a sign that there’s no basis for them except a dislike of users.