Okay, right: he did write that letter. Notice that it makes no mention of the grievances he mentioned in private and which I mentioned above, as it would have been unfitting for him to bring up such personal matters in this context. Historians all mention his wife’s prodding, Congress’s unmet financial obligations to him, and the thwarted attempt of General Washington to give him promotion to the Continental Army’s second-highest rank.
I suppose I should amend my previous comment to say that Arnold gave us no *candid* statement of his motivations–unless you accept that his motivation was entirely on the level of high politics. A chacun son gout.