We briefly mentioned how logic can be used to represent simple facts in the
last lecture. Here we will highlight major principles involved in knowledge
representation. In particular *predicate logic* will be met in other
knowledge representation schemes and reasoning methods.

A more comprehensive treatment is given in the third year *Expert
Systems* course.
**Symbols used**
The following standard logic symbols we use in this course are:

*
*

For allThere exists

Implies

Not

Or

And

Let us now look at an example of how predicate logic is used to represent knowledge. There are other ways but this form is popular.

dave@cs.cf.ac.uk