# MoL-2008-10: How to solve the conjunction fallacy? A discussion of alternative approaches

MoL-2008-10: Harten, Dewi S. (2008) How to solve the conjunction fallacy? A discussion of alternative approaches. [Report]

## Abstract

How to solve the conjunction fallacy?
A discussion of alternative approachees
Dewi S.Harten

Abstract:

Since many years, people have tried to understand and to model their
own behavior and language. This has proven to be a difficult, yet
rewarding task. Since the development of artificial intelligence and
robots, there is an actual use for this modeling, besides the sheer
happiness of understanding a part of our own existence.

One of the problems that we encounter when dealing with human
language, is our way of handling concepts and creating new, complex
concepts out of simpler ones. A concept can be seen as a mental
representation [the Stanford Encyclopedia of Philosophy, 2007]. For
example, let us consider a real life object ‘chair’. This is something
different from what we have in mind when we say the word
‘chair’. Because when we are talking about it, we are using a mental
representation and not the object itself. In other words, our mental
representation will probably be a prototypical chair, where the real
life chair does not need to be.

When we are creating complex concepts out of simpler ones, we are
actually trying to describe the complex object we see, by combining
two or more simple concepts that are already familiar to us. This
thesis will investigate the different possibilities to solve one of
the problems that occur when we are trying to create complex concepts:
the conjunction fallacy. The conjunction fallacy occurs when the
combination of two concepts has a higher probability than the original
concepts. This thesis will explore what research has been done through
the years in this field. It will define different ways in which the
fallacy can be interpreted and it will try to find a solution for the
conjunction fallacy.

I have divided my thesis into three parts. The first part handles the
different approaches to a solution for the conjunction fallacy using a
‘classical’ Boolean algebra.
The second part handles the more recent approaches that use a non-Boolean
algebra and geometrical models.
Finally, the third part contains the conclusion and future work.

Item Type: Report MoL-2008-10 Master of Logic Thesis (MoL) Series 2008 12 Oct 2016 14:38 12 Oct 2016 14:38 https://eprints.illc.uva.nl/id/eprint/805