10.31.2012

Jan Łukasiewicz






















"When I became aware of the incompatibility of traditional theorems of modal propositions in 1920, I was in the process of establishing a normal bivalent propositional calculus based on the matrix method. At that time I was convinced that it was possible to demonstrate all the thesis of the ordinary propositional calculus assuming that propositional variables could take on only two values, "0" (false), and "1" (true). This assumption corresponds to the basic theorem that every proposition is either true or false. For brevity's sake, I will refer to it as the law of bivalence. Although it is sometimes referred to as the law of excluded middle, I prefer to restrict this latter term to the well known principle of classical logic which states that two contradictory propositions cannot both be false at the same time.

Our whole system of logic is based on the law of bivalence, even though it has been fiercely disputed since ancient times. Aristotle knew this law, but he questioned its validity as it referred to future contingent propositions. The law of bivalence was flatly rejected by the Epicureans. Chrysippus and the Stoics were the first ones to develop it fully and incorporate it as a principle of their dialectic, the equivalent of modern day propositional calculus. The arguments regarding the law of bivalence have metaphysical overtones: its supporters are resolute determinists; whereas its opponents generally have an indeterministic Weltanschauung. Thus, we are once again in the area of concepts of possibility and necessity."

Setun

10.22.2012

Dívida

Schuld II


(...) Another significant aspect was that the debt service depended on how much the German economy could afford to pay, taking the country’s reconstruction and the export revenues into account. The debt service/export revenue ratio was not to exceed 5%. This meant that West Germany was not to use more than one twentieth of its export revenues to pay its debt. In fact it never used more than 4.2% (except once in 1959). In any case, since a large portion of the German debts were paid in deutsche marks, the German central bank could issue money, or in other words monetise the debt.
Another exceptional measure was that interest rates were substantially reduced (between 0 and 5%).
Daqui.

10.02.2012

Open source brick machine

How to change the world


Titica

4.ª carta aberta aos associados do Montepio

Ícaro


A pele que há em mim

Black dynamite

Agostinho da Silva

"- Oh, Amélia! Passamos o tempo cheios de projectos para a vida mas nunca deixamos a vida mostrar-nos os projectos que ela tem para nós .... (...) "
George Agostinho Baptista da Silva