First, some context. I'm a MSc student and I'm going to defend my thesis soon. The current plan is to submit the results of the thesis in two conferences: a less relevant result, which I'll call A, and a more relevant one, which I'll call B. So far so good, but here's the (typical) problem: who gets to be the first author? Me or my advisor?
Other answers to similar problems recommend a dialogue approach. I've already tried this, where I've written an email manifesting my interest in being the first author and why. The answer was that I could the the first author on result A, but he'd likely be the one in result B. Honestly, based on what I've read, I think my contributions for the work are weighty enough to justify my stance, and I'll try to persuade my adviser to change his point of view. Thus, my question is not whether or not I should talk to him (I already know I will) but how to make him change is view of the situation.
Below are some reasons why I think I should be considered the first author. Feel free to comment them or even disagree. If at the end of this there is strong evidence on why I should be just a co-author, I'll have no problem in changing my mind. Also, this pertains the result B, since there is not any contention about result A.
The paper will be an "enhanced" version of my thesis. What I mean is that the work will be basically the same, but with some extra simulations for which I didn't have time to complete by the thesis deadline.
As a consequence of 1., the text was written by me. However, my adviser has read it and provided feedback. The writing on the paper might have more contributions on his part, but most of the writing will still be me.
His argument is that the idea and the preparatory work came from his side. To be clear, he provided the topic (for which I applied and was accepted) and already had some literature review done. Also, some other previous theses were meant to provide results for this one (e.g. building of a database, or the study of a certain phenomenon). In the end, I used the database and cited some general results. However, most studies were in a non-applicable range for my work, so I had to devise an alternative (the result A that I mentioned above).
I can see where his argument comes from. That being said, it is also true that I significantly expanded his initial literature review and provided most of the work. He provided the initial setup and possibles issues, and gave me some tips and guidelines throughout the work (meetings normally twice a month, and sometimes emails in between), but never a definite solution. From there, I'd consider his feedback, research some more and try to provide closure to open questions. Some of these were pointed by him, some by me during the work. All the simulation work and required inputs (except the database mentioned in 3.) was either done by me or adapted from other sources (third party).
Of course he had a part to play here. I probably wouldn't be finishing my thesis on this specific topic if it weren't for him. That being said, I feel like that's what an adviser should do. His guidance was important, and I'm not trying to neglect that, but is it really enough to warrant him the first author spot?
Another important aspect to mention is that currently, we're on amiable terms and I'd like to keep it that way (as much as possible). Partly because it is always good to foster connections, but also because I haven't defended my thesis yet and he'll be on the jury. If this publication makes it through, this might be an important step in starting my career, so I want to fight some more.
Also, neither of us is having an imposing speech. What I mean by that is that nothing is set in stone, and there's still room for changes. At least, that was the idea I got from his speech patterns.
Disclaimer: Some journals do order authors by name. If this was the case, I wouldn't even be asking this question. However, the conference/journal we're targeting clearly distinguishes between first and second author.