I think in really seeking to answer this question the first thing we have to ask is what kinds of things define true masculinity. For instance, should we say that a man is defined by his belongings? By his appearance? By his abilities? Etc. What are the kinds of things that are important for true masculinity? This is, of course, a topic that many people spend time talking and writing about. However, I think that we can weed out a few of these on very basic grounds. First of all true manhood cannot be defined by one’s belongings simply because, if it was, a father could die leaving everything he owns to his 2 week old son and that 2 week old must then be considered a man. Obviously it is ridiculous to consider a two week old a man, and so we can throw out ‘belongings’ as a key to manhood without further question. The same argument could be used for position. If a king died and his 3 month old inherited the crown he obviously could not be considered either a man or a king, this is why we used to appoint regents. So, we can determine that traits which exist solely outside of the individual (i.e. money, status, reputation, etc) do not constitute the basis for manhood, and at the same time we can also conclude that age has at least some influence (even if only a negative one) on determining manhood. That is to say, while age may not be able to tell us who is a man, it can certainly tell us who is not a man.
Assuming then that manhood is defined by one or some combination of the internal qualities of a man we must determine what those qualities are. In brief these qualities may be listed as: appearance (or a man’s physical body), abilities (or the combination of his natural physical, mental, and social capacities), skills (or those facilities which he has learned through study and/or experience), emotions (or the feelings and moods that characterize him), and character (or the traits which affect his capacity and willingness to employ both his internal and external means to a task). Taking these in order we can first ask if appearance could be considered a test of manhood. Certainly men do have a distinct appearance and there are clear physical differences that distinguish males. However, there are also some males who are easily mistaken for females and vice versa. Clearly the normal distinguishing features of males and females used in everyday society (i.e. the presence of excess flesh in the breasts in females, or excess hair on the face, along stronger and wider builds and features in males) cannot be used as a determination of true masculinity because these features are not universal. There are men with excess flesh in the breasts and women with excess hair on the face. Similarly, the mere presence or absence of a penis cannot be considered a determination of true masculinity, because this returns us to the same problem as the external factors (i.e. infant males have them, but aren’t considered men).
Similarly, we must clearly reject abilities as a true mark of manhood because this would remove the enfeebled from the possibility of true masculinity. The history of the world is rife with males of inferior physical and social capabilities who can nonetheless be called great men, and certainly are true men. Franklin Delano Roosevelt is the first man who comes to mind. While his was physically enfeebled he stands still today as a giant in the minds of many. Certainly there are many others for whom the same could be said. There are many theological, mystical, and scientific figures of great stature who were socially inept or physically handicapped. The only ability that could potentially be considered here as a determination of true masculinity would be mental acuity (simply because I cannot think of an example to counter it), but I must reject even that because again a person of great intelligence may be a cretin and a worthless person. I will say that at a certain point, like age, intelligence may become a determining factor in what is not a man. For instance, a male with an IQ of ten is incapable of doing anything. He has an appearance, but no physical, mental, or social abilities, no skills nor the ability to accrue skills, and no character of which to speak. Thus we may conclude that this male is, for all intents and purposes, a child (at best) and certainly not a man. However, I think that this could only be used in extreme cases for those whose intelligence keeps them at a very low developmental level. For instance, I do not know of any culture modern or historical in which a five year old could be considered a man, and thus a male whose IQ would not allow him to develop past the capacity of a five year old could not be considered truly a man.
I think that’s probably enough for today. I’ll address the internal qualities of skills, emotions, and character later.