what would exclude someone from becoming a Mason?

Exclusion from Freemasonry is somewhat subjective, but with certain guidelines.  Certainly, the main things that would include you are if you are an atheist, a woman, are underage, or can be shown to be of poor character.  Other things that might exlude from membership are if the applicant is not sane or mentally unstable.

If there is something specific that you are worried may exclude you from Freemasonry, please contact one of us directly and we can answer your query.

Hi, Gerald-

The basis on which our potential candidates are judged is the content of the character.  Beyond meeting the basic requirements that Dan outlined, that is our only concern.  Any man not Constitutionally prohibited from membership (e.g., an atheist) who is deemed worthy of Brotherhood by the members of a lodge may be admitted.  Similarly, any man may be rejected.  There is no required uniformity among the lodges in Massachusetts regarding the questions a prospective candidate may be asked, or the evaluation of the responses.