“Interactivity. Many-to-many communications. Pervasive networking. These are cumbersome new terms for elements in our lives so fundamental that, before we lost them, we didn’t even know to have names for them.” Clever man Douglas Adams. You see he wrote this in 1999 and clearly understood, even then, the nature of the web so much better than most of us do even today.

As Douglas Adams points out the Internet is still novel – it’s very easy to forget that despite it’s incredible uptake the world has only had the Web since 1991. That’s really not very long. We are still getting use to it, still working out how to use it. But back in 1999 Douglas Adams clearly understood that one thing you shouldn’t be trying to do is model human trust and that’s because our brains do the job so much better.

Working out the social politics of who you can trust and why is, quite literally, what a very large part of our brain has evolved to do.

Although the Internet is a new technology, it is in many ways a return to a more traditional form of entertainment. The sit back and consume world of 20th century entertainment is the abnormality. TV, radio and the cinema are the aberrations because they aren’t interactive – all other forms of entertainment up until the early 20th century (and an increasing amount of entertainment since) are ‘interactive’ its just that we didn’t call them interactive entertainment because that would be silly – “a game of interactive cricket anyone?”

Unfortunately we currently looking at the Internet from the perspective of the non-interactive entertainment world of TV and radio. And that perspective isn’t helpful, as Adams puts it:

Newsreaders still feel it is worth a special and rather worrying mention if, for instance, a crime was planned by people ‘over the Internet’. They don’t bother to mention when criminals use the telephone or the M4, or discuss their dastardly plans ‘over a cup of tea,’ though each of these was new and controversial in their day.

Possibly because people see interactive entertainment as new and different they believe that they therefore need to build policies and models to express human trust into their web apps. The trouble is it just isn’t necessary – worse it doesn’t work. Our brains are great at working out who and what to trust – you just need to expose enough information so we can make the decisions. On the other hand it seems to me that attempts to formally model a trust network is a sign of hubris.

Of course you can’t trust what people tell you on the web anymore than you can trust what people tell you on megaphones, postcards or in restaurants… For some batty reason we turn off this natural scepticism when we see things in any medium which require a lot of work or resources to work in, or in which we can’t easily answer back like newspapers, television or granite. Hence “carved in stone.” What should concern us is not that we can’t take what we read on the internet on trust of course you can’t, it’s just people talking but that we ever got into the dangerous habit of believing what we read in the newspapers or saw on the TV – a mistake that no one who has met an actual journalist would ever make. One of the most important things you learn from the internet is that there is no “them” out there. It’s just an awful lot of “us”.

What you need then is not a model of trust instead you need a mechanism to answer back. You actually need a bit more than that – you need a mechanism to identify a person online – ideally wherever they appear on the web – via OpenID and FOAF for example. You also want to know who their friends are, or more specifically who claims to be friends with them. So for example, if I can see that someone is a friend of a friend I’m more likely to trust them than if neither I, nor my friends, have a connection with that person.

I also want to be able to read what they say and do online. If I can read their blog, look at their comments, check out their del.icio.us feed or twitter stream etc. then all the better. And since we are talking about online social networks this shouldn’t be too unreasonable.

Our brains are very good at processing this kind of social relationship information so we can assess whether or not we should trust a person, or more importantly to assess when and in which context to trust a person. I would trust Nick’s advice on say how to build my own home brew radio (in a lunch box) but not which pet to buy.

I remember Dan talking about the social graph and saying how he felt uncomfortable about the way XFN encouraged you to assert the nature of the relationship: “nope you’re not my ‘friend’ you’re an ‘acquaintance’ or ‘co-worker’ etc.” Which is why FOAF just has ‘friends’. This might be just because Dan is a nice bloke but I have to agree it is just a bit weird categorising the nature of your relationships the XFN way. But more pragmatically it’s also just not that helpful to model this information. All you really need is a mechanism to assert that there is a relationship and a URI to identify the person; you can then go and dereference the resource to work out whether you should trust that person or not for a given context.