What is Logic?

[logic2006]

L01.6 Formal and informal logic
Sometimes a distinction is made between informal logic and formal logic. The term "informal logic" is often used to mean the same thing as critical thinking. Sometimes it is used to refer to the study of reasoning and fallacies in the context of everyday life. "Formal logic" is mainly concerned with formal systems of logic. These are specially constructed systems for carrying out proofs, where the languages and rules of reasoning are precisely and carefully defined. Sentential logic (also known as "Propositional logic") and Predicate Logic are both examples of formal systems of logic.
There are many reasons for studying formal logic. One is that formal logic helps us identify patterns of good reasoning and patterns of bad reasoning, so we know which to follow and which to avoid. This is why studying basic formal logic can help improve critical thinking. Formal systems of logic are also used by linguists to study natural languages. Computer scientists also employ formal systems of logic in research relating to Aritificial Intelligence. Finally, many philosophers also like to use formal logic when dealing with complicated philosophical problems, in order to make their reasoning more explicit and precise.
L01.7 Further readings
• Entries on logic in the Stanford Encyclopedia of Philosophy - These are difficult pieces relating to the philosophy of logic.

[amoni]

waw
not wow but waw
so much information
for me logic is logic
you could not believe how many ppl think they are right and they think it is logic
and after scientifical evidence they turn to be wrong and the shock just appear in their face
last year i met science teacher in egypt who used to teach in elementry school i think 4th grade
and i was talking about how beautiful is the sky in that beach city and the talk draw to why the sky is blue
and he said it is blue because it reflects the color of water on earth
and i said what!!!!!!!!!!!are you serious
he said it is logical soultion
for my good luck there was a cyber cafe close by and i brough him a whole science page from unviersity website
that says sky is blue because electronmagntic radiation
and our human eyes
it is like if you live in New York everything seems to be logical
logic can be discussed to be proven
it is like theory
it is like muslims when you talk to them about mohmad and his weired actions and his use of the ppl minds
and it was not logical but now we are in 2006 and they think it is logic
God bless you