【COMP304 LEC1 LEC2】
LEC 1
1. Assessments :
2 Class tests (13% + 12%) and an exam (75%)
2. Module Structure: five parts:
a. Propositional Logic 1 week
b. Modal Logic 3 weeks
c. Epistemic Logic 3 weeks
d. Description Logic 3 weeks
e, Revision 1 week
LEC 2
1. Logics :
a. A logic is a formal system of reasoning. 逻辑是一种形式的推理系统
b. Any Logic comes in three parts:
(1. a language, that defines the well-formed formulas (wffs)
(2. semantics 语义 , that give meaning to formulas
(3. a deduction system, that allows us to find valid formulas
2. Propositional Logic
1. simplest logic
2. didactically useful 启蒙使用
3. too simple to handle concepts like time, knowledge, action, change and necessity
4. So usually too simple to be of practical use 不能实际运用
5. Propositional Logic: Language
a. Start with set P of atoms 原子, P = p, q, p1, p2.....
b. represent basic facts 事实真相 that we don't analyze further
c. Essentially: atoms determine the level of detail that we consider. 决定了我们考虑的细节程度
6. Propositional Logic: Language (II)
a. well-formed formulas (wff) are given as follows:
1. every p
P is a wff
2.
3. Nothing else if a sff
7. Notation :不影响意思的情况下尽量省略括号
8. Greek :
9. Pronunciation
注意那个 if...then 和 if and only if
10. Semantics
这个必须两个都一一对应 ，是相同的才是对的
这里then才是重要的，如果then的本来就对，那么前面的就不重要了；
如果前面是错的，then也是错的，那么这两个也是对的，因为在一个错误的条件下一个错误的答案那么这两件事情就是匹配也即是正确的
