Principle of identity. An object is the same as itself: A is A → A = A.
Principle of contradiction. Nothing can both be and not be in the same sense at the same time, or, in other words, contradictory statements can not both be true in the same sense at the same time: nothing can be A and not A → ¬(A ¬A) ∧ .
Principle of excluded middle. Everything must either be or not be, or, in other words, every statement must either be true of false: everything is A or not A → A v ¬A.
Logical
...THE KARL POPPER’S FALSIFICATIONISM TEXTO
The principal topic of this text of the Logical magazine of the scientific investigation is the vision that Popper has on the science, according to his falsificationism method. First the author argues that the science is not a sure knowledge and that for it it is not possible to reach the truth and that alone we can elaborate simple conjectures. It affirms that these scientific conjectures must surrender to rigorous and systematic tests, not to check them
...PROBLEMS OF THE HYPOTHETICAL-DEDUCTIVE METHOD
The formulation of hypotheses: it does not seem unreasonable to assert that in the formulation of hypotheses some factors come into play that may seem unscientific or completely away from scientific procedure, for example, imagination, luck or chance. The inability to respond to this explanatory gap has caused that some thinkers, such as Paul Feyerabend, have spread the influence of the imagination to the whole scientific procedure.
The validation and
...Text 1 summary
In this text, Descartes presents his analysis of ideas. First, Descartes says that our ideas, considered as immanent content (internal content) of our mind, cannot be considered as false.Then, after recognizing that we can only be wrong when we make statements, he says that it is a very common mistake to think that our ideas refer to external entities because, otherwise, we will never be wrong. Finally, Descartes concludes exposing his distinction between the three types of ideas:
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