Methodology of Philosophy

Scientists are constrained by the laws of nature but philosophers are constrained by the laws of logic

What logic is

Argument - set of propositions that are called premises which are put forward as a reason to believe another proposition called the conclusion. This is called a Syllogism

I want to get to London by noon. It is necessary condition to catch the 10 o'clock train to get to London by noon. The conclusion is catch the 10 o'Clock train

Deontic Kant- the logic of moral discourse. Lying is wrong therefore don't lie. (Only one premise and a conclusion). Note, straight from the premise and then to the conclusion but without the desire. (i.e. I want to get to London by noon). Lying is wrong therefore there is no desire. If you want to add to the desire to do right implies the possible desire to do wrong and in that case you really do not understand what it is to do right. i.e. You do not steal something not because you would be found out - you do not do it because it is wrong.

Are the premises true so we can accept the conclusion - Deductive. You have a good argument Are the premises true so that we have near certainly the the conclusion is valid - Deductive.

Modal Logic

It is not possible for vixens to be female then that vixen is not female. If it is not possible it can not be actual

Logic of Conditionals

If that is gold then I'm a Dutchman????

Possible Worlds

Kripke. You might argue that if German won the war we would be speaking German but what you can say is that German did not win the war and we are not speaking German. He postulates possible worlds where German did win the war. This is looking at the limits of possibility. But there is there a no possible world where a circle is a square because it is part of the definition.

Deductive and Inductive Arguments

With deduction it gives you a certain conclusion/validity Valid If it snows the mail will be late. It is snowing. Therefore the mail will be late

Invalid If it snows the mail will be late. The mail is late therefore it is snowing. You should always be able to find an alternative reason.

With inducton it does not give you ascertainment but gives you probability. Everyday the Sun has risen therefore it will rise tomorrow. This is very, very probable but it is not certain.

Arguments by Analogy

The Blind Watchmaker. The universe is like a watchmaker therefore the universe has a maker.