Wisdom is not the product of schooling but the lifelong attempt to acquire it. - Albert Einstein |
natural science: "how things are"
- knowledge about natural objects and phenomena
- primary interest: analysis
- examples: physics, chemistry
sciences of the artificial: "how things might be (and ought to be in order to attain goals and to function)"
- knowledge about artificial objects and phenomena
- primary interest: synthesis
- artificial things are as they are only because
of a system's being molded, by goals and purposes, to the environment
in which it lives
- examples: engineering, medicine, business, architecture,
painting
Definition of "artificial": human-made
as opposed to natural
questions: where does
mathematics / computer science / biology belong too?
claims by Simon:
- the world in which we live in today is much more a human-made, or artificial, world than it is a natural world
- a plowed field is no more part of nature than an
asphalted street - and no less
Alan Kay (Scientific America, Sept 84, p 57)
"molecular biology has the advantage of studying
a system already put together and working; for the composer of
software the computer is like a bottle of atoms waiting to be
shaped by an architecture he must invent and then impress from
the outside"
Definition:
Everyone designs who devise courses of action aimed
at changing existing situations into preferred ones. The intellectual
activity that produces material artifacts is no different fundamentally
from the one that prescribes remedies for a sick patient or the
one that devises a new sales plan for a company or a social welfare
policy for a state (Simon, "Sciences of the Artificial",
p 130)
examples: architects,
doctors, managers, politicians, teachers, ......
generic design - does it exist?
- design as an activity has a distinct conceptual
and cognitive realization from non-design activities
- it can be abstracted away from the particulars
of the knowledge base of a specific task or discipline and studied
in its own right
there is no definitive formulation of a wicked problem.
For any given tame problem, an exhaustive formulation can be stated
containing all the information the problem-solver needs for understanding
and solving the problem.
they have no stopping rule. In tame problems, problem
solvers know when they have done the job. Problem solvers terminate
work on a wicked problem, not for reasons inherent in the 'logic'
of the problem.
solutions to wicked problems are not "true-or-false",
but "good-or-bad"
every wicked problem is essentially unique
the aim is not to find the truth, but to improve
some characteristics of the world where people live
biology is the study of complicated things that give
the appearance of having been designed for a purpose
physics is the study of simple things that do not
tempt us to invoke design
treat complex human-made artifacts (e.g., computers,
airliners, cars, books) as biological objects
the behavior of physical, nonbiological objects is
so simple that it is feasible to use existing mathematical language
to describe it
a complex thing is something whose constituent parts
are arranged in a way that it is unlikely to have arisen by chance
alone
things evolve in response to some kind of selective
force
simple scheme of evolution:
- generate - produce variety (e.g. genetic mutation)
- test - to evaluate the newly generated forms (e.g.
natural selection)
problems with evolution:
- is myopic
- reaches local maxima (instead of global ones)
- moving away from a local maxima implies: going
across a valley
Design different from Evolution:
- guided
- there is a goal (question: can we design without a final goal in mind?)
- one can look back over a design and "clean it up"
- one can examine failures and see what went wrong
- faster than evolution (guidance, remembering previous
successes and failures)
Is Design the same as Evolution?
- "installed base" problem ("qwerty" typewriter, English measurement system, Fortran/Cobol, .....)
- standards
- knowledge is cumulative
claim: to design a complex
structure, one powerful technique is to discover viable ways of
decomposing it into semi-independent components corresponding
to its many functional parts. The design of each component can
then be carried out with some degree of independence of the design
of others, since each will affect the others largely through its
function and independently of the details of the mechanisms that
accomplish the function.
examples:
- functional programming
- object-oriented programming
- rule-based systems
- nearly decomposable systems
Simon:
in oil painting every new spot of pigment laid on
the canvas creates some kind of pattern that provides a continuing
source of new ideas to the painter. The painting process is a
process of cyclical interaction between the painter and canvas
in which current goals lead to new applications of paint, while
the gradually changing pattern suggests new goals.
Computer Science Technology Board:
system requirements are not so much analytically
specified as they are collaboratively evolved through an iterative
process of consultation between end-users and software developers
Rittel:
one cannot understand a problem without having a
concept of the solution in mind
one cannot gather information meaningfully unless
one has understood the problem but one cannot understand the problem
without information about it
going to the moon: a "complex" problem along one dimension; sources for success:
- exceedingly cooperative environment
- employing a single new organization
- single, highly operational goal
the American Constitution:
"the founding fathers did not postulate a new
man to be produced by new institutions but accepted as one of
their design constraints the psychological characteristics of
men and women as they knew them, their selfishness as well as
their common sense" (Simon)
1991: final design competition
1995: construction finished
requirement: 15 years without major modifications
question: a library in the year 2010? - books, CD
ROM, .... ---> we are not only designing for a given context:
we construct the context
client: city of Denver ---> committee (old librarian,
techi, ...)
who owns the problem??
- client(s), designers, customers, specialist, ......
- architect, structural engineer, contractor, bricklayer,
......
1st Generation (before 1970):
- directionality and causality
- separation of analysis from synthesis
- major drawback: perceived by the designers as being
unnatural; does not correspond to actual design practice
2nd Generation in the early 70'es:
- participation - expertise in design is distributed among all participants
- argumentation - various positions on each issue
- major drawback: insisting on total participation,
neglecting expertise possessed by a well-informed and skilled
designer
3rd Generation (in the late 70'es):
- inspired by Popper: the role of the designer is to make expert design conjectures
- these conjectures must be open to refutation and
rejection by the people for whom they are made (---> end-user
modifiability)
goals:
- bring task to the forefront
- analysis of work products
- goal sharing (for agents, critics, task-based indexing)
- information delivery
- learning on demand
- external simplicity through internal complexity
theory:
- collaborative problem solving
- distributed cognition
- integration of problem framing and problem solving
- reflection-in-action
- design-in-use
- situational awareness
- computational environments as "living"
entities
users:
- skilled domain workers
- stakeholders with different interest and different
background knowledge
General Programming Environments, e.g., Lisp, ...
-----> limited reuse
Object-Oriented Design, e.g., Smalltalk, Clos, C++, .
-----> lack of domain-orientation
Domain-Oriented Construction Kits, e.g., Pinball, Music Construction Kits
-----> no feedback about quality of artifact
Constructive Design Environments>, e.g., critics, explanations
----> design is an argumentative process
Integrated Design Environments, e.g., combining construction
and argumentation ----> lack of shared context
Multifaceted Architecture ----> limited evolution
End-User Modifiable Design Environments
user interface design - Framer
floor plan design for kitchens - Janus,
KID
graphics software - Explainer
computer network design - Network,
Pronet
water management - Cadswes
(with CU research center)
Cobol programming and service provisioning - GRACE
(with NYNEX)
voice dialog design - VDDE
(with USWest)
lunar habitat design - HERMES
(with NASA)
graphic arts, information design, information visualization
- Schemechart, Chart 'n'
Art
multi-media design environment - eMMa
(with SRA)
increase on the system's side
- domain-orientation
- construction
- specification
- embedded communication and history
- incremental formalization
increase on the user's side
- "back-talk" of the situation (critics, simulation)
- specification support through the argumentation component
- making argumentation serve design (providing arguments behind critiquing messages)
- access and delivery of cases (catalog examples)
relevant to the task at hand
technology is becoming powerful enough to get out
of the way (bring tasks to the forefront)
achieve external "simplicity" with internal
complexity (human problem-domain interaction)
information technology is a generic activity (ubiquitous
computing, clay) --->but: a "product / system"
will not exist until it enters a specific situation, where all
stakeholders will mold it to the work of a community of practice
information technology as a distinct category of
products will become invisible ---> it will dissolve into the
work itself
DODEs support "human problem domain communication"
DODEs are instrumental versions of systems that are
simultaneously user-directed and computationally supportive
critiquing
- breakdown as opportunities
- supports contextualized learning on demand
- makes argumentation serve design
seeds need to be functional enough that they are
used by skilled domain designers in their work
sociological structure of communities of practice
with power users and local developers
current limitation of DODEs:
- limited success models - specifically lack of experience with evolutionary growth in naturalistic settings
- tool mastery burden
research issue for DODEs
- design rationale
- case-based reasoning
- integrated artifact memories
- multi-user DODEs
- evolutionary growth through use
- new contracts between stakeholders
challenges
- the question is how - not why?
- how large or small, general or specific should a domain be?
- cost-effectiveness: powerful substrates are needed