A rather clever ancient Chinese general once wisely said "know thy enemy", and I couldn't agree with him more.
If you want to outwit your opponent, knowledge is power.
If Sun Tzu were alive today and had a Facebook account, I suspect he would count his enemies among his friends list, and be regularly studying the status updates and holiday snaps of all his greatest adversaries in the hope of somehow using the information in his next strategic battle plan.
But as Facebook evolves (and not, I might add, in the positive way that word implies), he might have chosen to add "don't know thy friends" to his most famous utterance.
That's because while knowledge may indeed be power, too much knowledge - especially about one's friends - is simply a disappointment.
Back in the good old days all of eight years ago when Facebook was the domain - both literal and figurative - of a geeky group of net nerds working out of a university dorm room, friendship was something cultivated slowly and valued deeply.
One of humanity's oldest institutions, it was earned the hard way through the investment of time, the pursuit of common interests and the respect and gratitude that comes from getting help when needed and giving it back in equal measure.
Friendship was a valuable commodity.
Now, especially among young people, it is becoming a worthless currency. "Friendship" is acquired by the click of a mouse and dismissed just as easily with another one.
And instead of a slow burn that sees a new friend selectively unfurl the layers of their lives as the friendship develops, we get instant access to not just the holiday snaps (let's not mention the birth photos, let's just not even go there) but far too often the internal monologues of people's minds.
And I say "internal monologues" because before Facebook, that's just what random thoughts were, and it's where I believe they should have stayed.
It is an understandable human flaw that we're all inclined to speak before we think sometimes, but irregular contact with friends provided a fabulous filter, allowing us to consider and organise our thoughts before we shared them.
Now they are tapped out on a keyboard and published online in perpetuity before the smart parts of the brain have even had time to fire up. The result - at least for me - is that I now know far more about some of my friends than I really want to.
Some who come across as intelligent and quick-witted in real life undermine that via their virtual one, and others who exude a dignified sophistication in person unravel it all with I am selfies that seem hilarious at tequila time but somewhat less so when their friends log in to Facebook on a sober Sunday morning.
I've learned from my own experience that the best status update is always the one shared over a coffee every couple of weeks with a (real life) friend, rather than the one you share with 400 "friends" when you're sitting at home alone in your undies.
And the best and most enduring friendships are not those acquired by the click of a button, but forged through shared triumph and tragedy and a genuine investment of time.
My favourite line from my all-time favourite poem, The Love Song of J. Alfred Prufrock reads, "I have measured out my life in coffee spoons".
I have no doubt that TS Eliot would agree with me that it is the friends that watch you stir those spoons and listen to you talk as you do so that are the ones that count.