zoxiy user guide
--- by firstname.lastname@example.org
Some notes on using zoxiy to complete logic exercises (writing proofs, creating counterexamples, ...).
There are logic exercises associated with each lecture. This is how to complete them ...
proof ex-proof ex-trans
When you use zoxiy you can type words instead of using symbols. But which words stand for which symbols? Here’s a list.
Introduces the notion of identity used in studying first-order logic. Includes example argument and the two principles. Also demonstrates how to assign names in zoxiy, and using zoxiy to make identity statements true and false.
Illustrates and defines the terms ‘contradiction’, ‘logical truth’ and ‘logical possibility’. Describes how to recognise these from truth tables. Demonstrates using zoxiy to construct truth-tables and answer questions about contradictions, logical truths and logical possibilities.
Explains how to do proofs involving quantifier rules with zoxiy. (Where you need to put the name ‘a’ in a box, write ‘[a]’.)
Describes how to create possible situations in logic-ex.
Explains the notion of a counterexample. Discusses a counterexample to a simple argument. Demonstrates using zoxiy to construct a counterexample involving shape and size properties.
Introduces and illustrates the use of rules of proof for conjunction. Explains how to create proofs using logic-ex.
proof proof-example ex-proof
Introduction to the rules of proof for →, →Intro and →Elim. This is the first time subproofs are used. Also illustrates a proof without any premises. The proof is from premises P→Q and Q→R to conclusion P→R.
Defines the predicates such as ‘Happy(x)’ and ‘Crying(x)’ used in creating possible worlds.
A quick guide to creating possible situations in zoxiy.