"We keep half of what we think hidden away on our inside and only deliver ourselves of that remnant of it which is proper for general consumption." - Mark Twain
"It were not best that we should all think alike; it is difference of opinion that makes horse-races." - Mark Twain, in Pudd'nhead Wilson's Calendar
"I am not one of those who in expressing opinions confine themselves to facts." - Mark Twain
It must be pointed out, at least in regards to the first question above, that Mark Twain shared his opinion of the opinion-delivering habits that belonged to the general "We" well before the Internet and Facebook made opinion-delivering easy, fun, and relatively anonymous. These days anyone with an e-mail address (real or faked, often) can crawl onto a web-based forum and share all sorts of opinions in all sorts of ways that would've made a Twain-era sailor blush in shame.
The practice of sharing your opinion so openly and freely has interesting implications for authors, especially in a world that has become so emotionally-charged in its consideration of political issues.
Specifically: do you, or don't you?
Don't!, the common wisdom cries. Everyone knows that we authors want people reading our books no matter their political leaning. And it's true; each time I see the number sold column in the KDP report increment I'm both happy and happily heedless of whether the purchaser was a scumbag right-wing capitalistic fascist pig or a freaky left-wing pinko commie tree-hugger. Right? And the inverse is true as well; the last thing I want is for someone to not buy my book because he knows I have political or religious beliefs that swing opposite to his own.
Granted, the lessons on opinions and business are prevalent throughout the business world. Both The Huffington Post (an admittedly left-wing publication) and Forbes (an admittedly right-wing publication) published articles linked here that described the pain the Papa John's, Denny's, and Applebee's brands all went through when their chief executive staff decided to open up to the public their opinions on a fairly business-oriented yet highly politically-polarized topic. Both articles can be summarized fairly simply: "Ouch, man, that frickin' hurt." Just don't do it, the message is--business is business is business, and it should never be combined with politics.
It must be noted that these brands are all national, with millions, if not billions, of dollars of cash in reserve. What's a poor Indie author, who looks forward to his next Remittance Advice from Amazon as my Chihuahua looks forward to her next full food bowl, to do?
My recommendation? Be real.
First of all, I'm not saying be stupid. Separate your brand from your private Facebook. My own web page has the most boring of news on it; all of that crap is completely unrelated to the newest information regarding the Benghazi attack or the health care law or anything else you'll read about on CNN. Granted, when "The Other Stephen King Wins ____ Award" is on CNN, you bet my site will match, but that won't be political. When I Tweet, as I often do, it's either a business-related Tweet or a quote of the day or something about Survivor, or something--anything--else but politics. My writing is not about politics, period.
On my personal page, though, I do express my fairly strong opinions. With that said, I have to say I've never seen a dip in sales as a result of doing so. That's most likely because I've separated the brand from the person.
Besides, nearly everybody on my Friends list has either bought my
books, or not bought my books, and they're very unlikely to cross the
line between the two options.
That said, I've also tempered my own opinions over time. It's not a business move, but rather a personal one that kinda follows along with the logic of Twain. Years ago, before Facebook, I was a member of my West Point class's listserv. I found a particularly left-leaning Bill Maher quote funny, and I posted it there, and oy, vey, was there a backlash. As Facebook rose in popularity I made friends on both sides of the spectrum, and in turn I lost friends on both sides of the spectrum as I leaped in with both feet and shared my opinion.
I'm showing far more restraint these days, though. A friend posted a thread recently that complained about a televised crowd not rising entirely for the National Anthem--a complaint I'll share. But in five or six comments the thread had denigrated to blaming that behavior on the President. I read, thought about replying, and then continued scrolling. Nice job, right?
It's hard, though, as an author especially, to not have an opinion, and it's also hard to not bring your powers of linguistics to bear in expressing that opinion. To a certain extent, though, it's a requirement.