This course is about the theory
and realisation of so-called intelligent agents, pieces
of software that display some degree of autonomy, realised
by incorporating `high-level cognitive / mental attitudes' into
both modelling and implementation of this kind of software. As
such, the subject of intelligent agents is at the cross-roads of the
fields of artificial intelligence and mainstream computer science,
in particular software engineering. These mental attitudes comprise
'informational' and 'motivational' ones and are often of the so-called
BDI kind, dealing with 'beliefs', 'desires' and 'intentions' of
agents. The agent concept calls for an integration of several topics
in artificial intelligence, such as knowledge representation
and reasoning (in particular reasoning about action and change)
Agent technology, as the field is
generally called, has a great potential of applications,
ranging from intelligent personal assistants to e-commerce
and robotics (where in the latter case often the term 'cognitive
robotics' is used).
In the course we will devote much
time to the philosophical and theoretical (mostly logical)
foundations of the area of intelligent agents, and then
go on with describing ways of realising them by special architectures
and so-called agent-oriented programming languages in which
one can program the 'mental states' of agents. This course
presents the introductory theory for the agent-directed courses
in the Master programme and gives a background for courses such as
MAS and MAP.
Docent / Lecturer
Downloadable at the moment:
(John-Jules Meyer, Agent Technology, in: Encyclopedia of Computer Science
and Engineering, Vol. 1 (B.W. Wah, ed.), Wiley, Hoboken, NJ, 2009, pp.42-49.
Modal Logics for Intelligent Agents (John-Jules
BDI Logics (Meyer, Broersen & Herzig)
Intelligent Agents by Michael Wooldridge
Levesque, H.; Pirri, F.; and Reiter, R. 1998.
Foundations for the Situation Calculus
(only background, no
direct material for exam)
paper in JAAMAS
(material upto and including
(P.R. Cohen & H.J. Levesque,
Intention Is Choice with Commitment, Artificial
Intelligence 42, 1990, pp. 213-261.)
Rao & Georgeff
(A.S. Rao & M.P. Georgeff, Modeling
Rational Agents within a BDI-Architecture, in Proc.
KR'91, Morgan Kaufmann, 1991, pp. 473-484.)
(W. van der Hoek, B. van Linder & J.-J. Ch. Meyer, An Integrated Modal
Approach to Rational Agents, Report UU-CS-1997-06, UU, 1997; also in: M.
Wooldridge & A. Rao (eds.), Foundations of Rational Agents, Applied Logic
Series 14, Kluwer, Dordrecht, 1998, pp. 133-168) and
(J.-J.Ch. Meyer, W. van der Hoek & B. van Linder, A Logical Approach
to the Dynamics of Commitments, CKI Preprint Series No 14, 1999, also in:
AI Journal 113, 1999, pp. 1-40) are the basic papers on KARO
(Y. Shoham, Agent-Oriented Programming, Artificial Intelligence 60 (1),
1993, pp. 51-92) (only background, no direct material for exam).
Slides are downloadable. However,
some caution is in order: due to fonts used on my machine
printing errors may occur (e.g. deleted or wrong symbols). Unfortunately
this is unavoidable. So, always check your prints.
Modal logic II
Errata:: p 251, Thm 7.2, 3rd line:
"INTEND2" -> "INTEND1"; pagina 236, prop 4.2, first part of first clause
"p \/ q". should read "p /\ q".
(Slides on informational attitudes are not examination
(STRIPS IS NOT EXAMINATION MATERIAL)
(Examination material: upto and including slide 23!!!)
Erratum: p 14, def 9: in conclusion of transition rule:
"\pi" should read "\pi \eta"
example AGENT0 program
example 3APL program
Regularly homework will be given
to enable you to practise with the material and prepare
yourself for the examination. This home work will be discussed
(partially) during the werkcolleges. It does not give you direct
credits for the examination. It is only for necessary practice.
1. Think about the realisability of
Asimov's laws of robotics. How difficult are they? What
kind of AI techniques are necessary to be able to implement
2.(a) Show the validity of the basic
property on slide 67, i.e. show that it holds in any world in any
(b) Prove the correspondences of slide 70 in the following
sense: show that Kripke models that satisfy the respective conditions
on the accessibility relation R make the corresponding modal
formula true in any world.
3. Prove Prop 3.15, 3.16, 3.21, 3.22,
3.23, 3.26, 3.28 of Cohen & Levesque formally, using the
definiition of the semantics.
4. Prove Prop. 3.8, 3.9, 3.11, 3.13, 4.5
(as precisely as possible). Challenge: does Theorem
7.2 hold for any actions a and e?
5. Prove Prop. 3.8 and 3.9 of Cohen &
Levesque again, but now in the framework of (P)LTL (this is
6. Check whether the following formulas are
valid in CTL*:
(a) A psi -> E psi (b) E box psi ->
A diam psi (c) A diam psi -> E box psi
7. Construct BDI-models Rao & Georgeff-style
for the following formulas:
(a) GOAL(optional \Box p)
(b) optional \Diamond inevitable
\Box GOAL p
(c) inevitable \Box optional
\Diamond GOAL p & ¬(optional \Diamond inevitable
\Box GOAL p)
8. (a) Prove the validity
of GOAL(alpha) -> BEL(alpha) for alpha = optional(psi)
under the B-G condition (see slides).
(b) Prove Theorems 1 and 2
in the article of Rao & Georgeff.
9. Show that in dynamic logic
(and so also in KARO) the following holds:
(a) |= [alpha1 ; alpha2] phi
<-> [alpha1]([alpha2] phi )
(b) for deterministic
alpha: |= <alpha>(phi & psi) <-> ( <alpha>phi
& <alpha>psi). Also show that this does not
hold for general alpha (that may thus be non-deterministic)!
10. Regarding KARO logic:
(a) Show |= A(alpha1 ; alpha2) <-> A(alpha1)
& [alpha1] A(alpha2) under the condition for function C on slide
(b) Show for deterministic, non-failing
actions alpha1 and alpha2 the validity of:
Can( alpha1 ; alpha2 , phi ) <->
Can ( alpha1 , PracPoss ( alpha2 , phi ))
(Hint: first show that now it holds also that:
A( alpha1; alpha2 ) <-> (A alpha1 & <alpha1> A
(c) Show: |= phi -> psi does NOT imply |= Goal(phi)
(d) Prove the first 3 validities
on slide 166 (using the semantics on slide 165).
(e) Compare the logics of Cohen & Levesque,
Rao & Georgeff and KARO. What are similarities and differences?
11. Exercises situation calculus
and STRIPS planning
(downloadable Word document)
12. (a) Prove the Theorem on slide 18 of Thielscher.
(b) Exercise about regression
in situation calculus
(downloadable Word document)
13. (a) Compare deliberative and reactive agent
architectures: what situations call for which architecture?
(b) Discuss the problems occurring when realising
a layered hybrid agent architecture, and how to solve these.
(c) Discuss (dis)advantages of horizontally
versus vertically layered hybrid agent architectures.
14. Consider the following exercise:
(downloadable Word document)
Sample elaborations of homework
Here you can find a couple of elaborated exercises to show how this
should be done: 3.15c
There will be a written examination
which is ' limited
open book' , i.e. only
clean (non-annotated) versions of the study
material (slides, copies of articles) may be used.
HOWEVER THE ELABORATION OF THE HOMEWORK EXERCISES AS PROVIDED AT
THE INSTRUCTION HOURS IS NOT ALLOWED!!! A sample exam can be
For persons who (think they) do not
have sufficient background in (modal) logic (as e.g. been
treated in courses like Logic for AI), I recommend to study
the first two chapters of the book Meyer & van der Hoek, Epistemic
Logic for AI and Computer Science . (This also contains exercises
with answers.) By now there is a paperback version of this book,
but it should also be available in the library.
File last modified at
OCTOBER 23, 2012