There are three sorts of "we" in business. There is the we that executives use to show that everyone is one happy family. There is the new fashionable we about crowds and social networks. And there is the traditional we that refers to we, the workers.

The first we is phoney and to be avoided. The second is interesting, if a little over-rated. The third, though deeply unfashionable, is essential, and any manager who doesn't understand it isn't going to get anywhere.

My interest in we has been whipped up by two books on my bedside table: We Are Smarter Than Me: How to Unleash the Power of Crowds in Your Business, which is all about We 2, and the cult novel Then We Came to the End, which is a definitive guide to We 3.

For We 1, the pompous we of the executive, no new book is needed. The seminal text is a memo written a few years ago by Geoff Boisi, who was head of investment banking at Chase. In it he urged all employees to stop using the first person singular and go for we instead because it would help them "share problems and dreams in candour and confidence". His reasoning went like this: "We means teamwork. I is a one-man band."

This is triple-A drivel. Investment bankers don't want to share dreams. They want to do deals and get big bonuses. They are a fiercely individual bunch and should stick with I.

As for the We 2, the trendy we of the social network, the book We Are Smarter Than Me (to be published in October) breaks new ground because it is not just about the power of crowds, it is actually written by one. It argues that networks are changing the rules of business and, to prove the point, has changed the rules of publishing. Rather than paying a whacking advance to one author, it has invited everyone to contribute to the book on the web. Any royalties will go to charity.

At the most basic level, I am all in favour of We 2 if it means getting other people to do your work for you and failing to pay them. Indeed I consider myself to be a pioneer in this area. On Wednesdays I write an agony aunt column in which I invite readers to do half the legwork by sending in problems and writing answers to other people's problems.

However, what I don't like about We 2 is the wide-eyed, quasi-religious way people talk about it. There is a lot of stuff about "harnessing the power of community", which is the sort of phrase that makes one want to be a hermit.

In spite of the breathy talk, I'm not convinced We 2 is really as popular as all that, or that social networks are actually changing the way most business is done. I've just looked at the wearesmarterthanme website and under the heading "Buzz" is a blog called Age of Conversation, inviting comments. The number of comments when I last looked: zero.

By far my favourite is We 3, which is the natural, colloquial used by a group of workers. This pronoun is at the centre of Then We Came to the End, a novel about cubicle dwellers in an advertising agency.

The book is written by one man, Joshua Ferris (who is now getting large royalties in the traditional fashion), and who has chosen to tell the story in the first person plural throughout.

"We were fractious and overpaid . . . The world was flush with internet cash and we got our fair share of it.

"It was our position that logo design was every bit as important as product performance and distribution systems," it begins.

At first the we is awkward and unnatural. But as you read on, it becomes clear this isn't a gimmick: we is vital to understanding how an office actually works.

It is a reminder that in every office a group of people are stuck together for an improbably large number of hours, day in, day out.

Together we all experience the crashing of IT systems, together we are at the mercy of decisions made by managers, together we enjoy the arrival of fresh bagels and together we share the fear of getting fired. We doesn't imply teamwork, or happy families, or even people who like each other.

It is simply the mundane experience of office life in close proximity that turns lots of Is into one we.

The salient point about the novel is seeing who is outside the we. Weird or disliked colleagues are inside, but managers are not, even the ones who are popular and seem like nice people.

This is a pretty basic truth, yet is one that many managers misunderstand. Bosses who think they can go to the canteen and sit hugga-mugga with everyone else are making a big mistake.

I know someone who has built up a large and successful communications business. She is clever and informal and funny and just the sort of person you would expect to be liked by everyone.

And what does she say about her employees? That they are all a big happy family? No, she says that the secret to her success has been always to know she is an outsider. Her favourite piece of advice to managers: to give people room to gossip about you behind your back. She knows that there is a we.

And that the we will never include her.