“Some men …”?
Philosophers? “Does a falling tree make a sound if there is no (man) there to hear it?”
Quantum Physicists? “Is the moon there when no (man) looks?” http://www.theory.caltech.edu/classes/ph125a/istmt.pdf
If not, if they are regular ole Joe Shmoes, I’ll hazard their real concern (warranted, in my opinion) is that they don’t exist unless there is a woman there to observe them.