End of First-Order Logic.

Aren't you happy? If somebody is

unhappy about the end of First-Order Logic,

i.e. is interested in logic,

we do research in my group on logics,

and on using logics to do complicated stuff.

All of that was very easy.

So there's a course next semester on using logic for math.

Where you learn really a lot of

logic for complicated matters like mathematics.

If you're interested in doing any logic related research or so,

come and talk to me or come through the course,

and then you can try it out without talking to me,

and see what it's like.

Okay, good. New topic.

So I would like to still get a little closer to agents.

The problem solving that agents have to

do when there's time involved, we call planning.

Time changes the whole thing a little bit.

We had very, very simple notions of time so far.

We did our problem solving in

an offline process where we just basically

developed a solution or a plan beforehand,

without really taking time too much into account,

or other agents or so except for the games.

That's something I would like to change.

The main thing is going to be that we want to use

our inference level approach,

which is about describing the world,

which was good because it allowed us much more efficient

reasoning processes and flexible reasoning processes.

We want to apply that to essentially search problems again.

Remember in the search problems,

we had atomic states.

In search, we took a step into another atomic state.

Now, the problem of that is if we try and think about it,

from the logic perspective,

is that it's no longer true that whenever we've deduced something,

it stays true.

So far, we had this monotonicity of logic built into everything.

If I ever deduce that P is equal to NP,

P will be equal to NP from now on, and I know that.

Now, think about traveling in Romania.

We start out with the knowledge, I'm in Arad.

Then we go to Sibiu,

which is nice because we have a new fact, I'm in Sibiu.

Unfortunately, we also have another new fact,

I'm no longer in Arad.

See, something is happening.

So the problem, if we want to apply logic and friends,