Argument about history

Person 1: This historical figure was gay. 

Person 2: This historical figure was not gay. 

Person 1: How do you know, he could have been, what reason do you have to think they weren't gay? 

Person 2: Because I have yet to see any sufficient evidence to suggest any homosexual tendencies from this person. 

Person 1: What do you mean by homosexual tendencies? 

Person 2: Feelings towards members of the same sex that have romantic or sexual connotations. 

Person 1: That doesn't mean they weren't gay. 

Person 2: You're right, but you still have yet to demonstrate how they were. 

Person 1: Well what about these letters that they have in correspondence with this person, they surely demonstrate romantic, if not sexual feelings between them. 

Person 2: First off, you have to understand the greater historical context. Not everyone engaged in similar means of affection in the past as we do now. Not to mention this was during a time when people could be more poetic with their words, and affectionate in ways that might be construed as gay today, but really in the time they were living, could also be seen as a demonstration of friendship. 

Person 1: Oh that's just something most historians say because they're blinded by their heteronormative worldview, and can't handle the idea of someone in history they know before as not being gay, being seen as gay, so they try to interpret it as something else to shield their fragile minds from uncomfortable truth. 

Person 2: Even if I were to grant you an author is building their case based on the foundation of prejudice, that doesn't mean that their perspectives are invalid right off the bat. And just because your interpretation potentially opens up the possibility of a new historical figure being claimed as gay, which I can't help but think given the current political climate, you are also driven by a bias for this person to be gay because it then further validates your existence in history, and by extension your existence in the contemporary world, but that still doesn't make you any more right than them. 

Person 1: Why are you so against the idea of this person being gay.

Person 2: I'm not against the idea of them being gay, I'm just saying you haven't provided sufficient evidence that they were. 

Person 1: That still doesn't mean  they were straight. 

Person 2: Perhaps, but when all other signs of their life seem to point to that they had not inclinations of a sexual nature towards the same sex, but the opposite given A) Their writings on their interest in women.

B)Their musings on the beauty of the opposite sex and C) The fact that they were married to someone of the opposite sex for x amount of years, would not suggest anything else but what can be considered a heterosexual proclivity. 

Person 1: Well any evidence of them being gay has been suppressed by previous historians. 

Person 2: What is your evidence of that? 

Person 1: It has been done before. 

Person 2: Right but what evidence do you have that is happening in this case? 

Person 1: God why do you have such a problem with gay people being in history? 

Person 2: I don't have a problem with gay people in history, I have a problem with people making claims that something is true without something to back it up. 

Person 1: God you are such a homophobe. You wouldn't feel the need to counter my point of view unless you had an inherent issue with the idea of them being gay in the first place. 

Person 2: Are you saying straight people don't exist? 

Person 1: Of course not, I know a lot of straight people. 

Person 2: If you know that straight people exist, then why is it such a problem believing that this historical figure was straight? 

Person 1: Well I mean it really doesn't matter anyway, all these labels are just bs constructs constructed by a cis white heteronormative patriarchy hell-bent on creating labels so as to divide us. So when you think about it, nobody is really anything.  

Person 2: What? If it's all bs then what the hell have we been talking about this whole time? 

Person 1: Whatever, see you later. 

Person 2: What just happened. 

I read the first 1/2... I think that is all I need to identify the problem. Nobody is defining "gay." They might as well be arguing about if the person was "flitteryfluff" of not. For example,

"One is considered 'gay' if they identify as gay or a similar, culture/context appropriate term (e.g. 'homosexual')."

or

"One is considered 'gay' if they were known (well documented beyond reasonable doubt) to have sexual relations with a member of the same gender."

This would be a good starting point.

I only dabble in historical topics like this, but I'm seeing both sides using generalizations and hypotheticals (with fallacies mixed in on both sides) in an attempt to prove their points. These, by themselves, don't have much substance to them, but in some cases could be the basis of a strong argument if there was more evidence to back it up.

I think the way a historian would approach this question would be to interrogate the historical record. Come up with a model of the attitudes towards homosexuality and same sex relationships at the time and place where they lived. Look at how the record of the person in question fits into that, and how it compares to what would have been considered normal behavior. Consider the validity of the sources you're using. Prepare to have every part of your argument nitpicked. Your finished argument might wind up being an entire book, and even then you may not really be able to prove your point conclusively.

Ah, an exhibition of, as the French would say, mental masturbation. 

Oh, the intrigue of historical figure's love lives. If gossip magazines existed during the Renaissance, I'm sure they would be overcrowded with "Was Da Vinci Gay?" or "Michelangelo's Secret Crush!" speculations. Person 1 and Person 2 here are doing their own time-traveling tabloid investigation.

Person 1 really hopes this historical figure was completing the trio of musical preference: 'Composes, Plays and Loves in Major and Minor'. Person 2, on the contrary, seems to place him pretty straightforward on the straight and narrow path, with some baroque reasoning of historical language and confounding context.

Just when you think they're stuck in an infinite loop of 'is-he-isn't-he', Person 1 pitches that historians have been playing a centuries-long game of 'hide the rainbow', suppressing any evidence of their beloved figure's homosexuality. Person 2, of course, demands a receipt for this claim, only to be blindsided by straight-bashing accusations. Remember kids, not providing sufficient evidence can lead to you being called a homophobe by History Detective Enthusiasts!

Finally, just as you think this passionate discourse might reach a logical conclusion, Person 1 declares that all labels are mere constructs created by cis white heteronormative patriarchy to divide people. Cue record scratch and Person 2's palpable confusion. All this debate when 'nobody is really anything'? Surely, we need a refund for that precious wasted time!

But fear not as Person 2 isn't entirely innocent in this twisted tale of historical orientations either. They do seem to be entirely happy assuming someone's straightness without solid proof, conveniently forgetting that being married to someone of the opposite sex could just be due to societal pressure or personal pretense!

But before we have time to figure out who's more illogical here, Person 1 calls it quits, leaving us all in a state of amused bewilderment that closed the conversation with a historically funny note. And thus ends another day in the intriguing world of historical figure's sexual orientation speculation! Just another day at the office for these historians, I'm sure.