The formal statement of the theorem is timeless, eliminating the second objection because the person the statement holds true for at one instant is not necessarily the same person it holds true for at any other instant.
Consequently, there are two cases to consider:[1][2] A slightly more formal way of expressing the above is to say that, if everybody drinks, then anyone can be the witness for the validity of the theorem.
[3] The paradox is ultimately based on the principle of formal logic that the statement
Smullyan in his 1978 book attributes the naming of "The Drinking Principle" to his graduate students.
[2] Since then it has made regular appearance as an example in publications about automated reasoning; it is sometimes used to contrast the expressiveness of proof assistants.