This week, Professor introduces Conjunction and Disjunction to us. Conjunction and Disjunction are both used to connect statements. However, they "combine" the statements in quite different ways.
For the statements
combined by conjunction, the whole sentence is true only when all of the
statements are true. If any one of them is false, even though the others are
true, the whole sentence is still false. For the statements connected by
disjunction, the requirement for the whole sentence to be true is that at least
one of the statements is true. It will be false only when all the statements
are false.
This makes
conjunction and disjunction sound like the English word "and". Indeed, conjunction
is a logical "and", but the English word "and" is sometimes different. English
causes ambiguity, the examples can be found in Professor's ppt material. The "inclusive" and "exclusive" example is pretty good.
A difficult part
for me of this week is De Morgan's Law. At first, I cannot understand this law,
so I just try to memorize it. This leads to the fact that I spent much time in
doing exercises because I need to think a lot even in very basic question. For
dealing with this problem, I carefully read our online notes. According to the
guide, I drew some Venn diagrams about different expressions. After drawing
Venn diagrams, I clearly saw that the same meaning can be expressed by
different ways. This helps me deeply understand De Morgan's Law and is also very
helpful for me to use conjunction and disjunction.
At the end, I
just want to remind that assignment 1 will be due in very soon. Hopefully
everyone gets a good mark.
See you next week :)
Cecilia
No comments:
Post a Comment