"[I]t is the frowzy corrupt air from animal substances and the perspired matter from our bodies, which, being long confined in beds not lately worn... [that] obtains that kind of putridity which infests us, and occasions the colds observed upon sleeping in, wearing, or turning over, such beds [and clothes." -Benjamin Franklin in an argument with John Adams over whether to sleep with the window opened or closed in a room that they shared on a diplomatic trip to France.
"As time passed and his French improved, Adams further realized that Franklin spoke the language poorly and understood considerably less than he let on." -David McCullough author of John Adams.
If you think about the "Founding Fathers" as a serious group of men who only argued about the big picture ideas they needed to hash out in forming a new nation, learning a bit more about the relationship between John Adams and Benjamin Franklin may challenge that notion. Like anyone else, these were men with quirks, passions, and personal opinions about each other. Benjamin Franklin and John Adams had vastly different outlooks on life. Adams was a frugal man who believed in simple accommodations. Franklin was interested in experiencing the world as evidenced by his travels, inventions, and discoveries. As a result of their different approaches to life, Adams sometimes saw Franklin as someone who was simply in France to enjoy himself. Like beauty, many things are in the eye of the beholder. Most contemporary people would not think of Ben Franklin as a slacker, but apparently, at times, at least one of his contemporaries sometimes did.
Or perhaps a bit of jealousy was involved. According to the John Adams biography by McCullough, while Adams was not impressed by Franklin's mastery of French, his French "admirers" found Franklin's "odd pronunciation...but another part of his charm." Adams, on the other hand, could never feel comfortable in France and was not as well-known or well-regarded as his countryman.