No argument can force us to accept the truth of any belief. But a valid deductive argument can force us to choose between the truth of its conclusion on the one hand and the falsity of its premises on the other. 
Category Archive: .Notturno, Mark
But if ‘2 + 2 = 4’ is true, then it follows that ‘2 + 2 = 5’ is false—and that ‘2 + 2 = 6’ is false, and that ‘2 + 2 = 7’ is false, and so on. But if these statements are false, then the statements ‘“2 + 2 = 5” is false’ and ‘“2 + 2 = 6” is false’ and ‘“2 + 2 = 7” is false’ are one and all true. And it is easy to see that we can, in this way, generate an infinite number of true statements that are of no interest to science at all, or to anyone else for that matter. 
Earlier I said that Popper believed in absolute and objective truth. This is very easily misunderstood, especially if we equate a definition of ‘truth’ with a criterion of truth. But whether or not truth is absolute has nothing whatsoever to do with whether or not we have a criterion for determining what it is. ‘Absolute’ simply means that something is not conditional or relative to anything else. Popper thought that truth is absolute in just this sense. Being true is different from being-believed-to-be true. It is not relative to or conditioned by what anyone believes. And it does not depend upon a theory, or evidence, or a historical context, or anything else—except the facts. 
In my view, trying to measure verisimilitude by counting a theory’s true or false consequences always missed the point. Every false theory has the same number (if we can really talk this way) of true and false consequences as every other. This is a consequence of the truth-functional nature of our logical connectives and the truth-functional definition of validity. But some false statements are still closer to the truth than others. 
Whether we should work with a theory that we know to be false or eliminate our error will depend almost entirely on our alternatives, and on the problem that they are supposed to solve. 
The primary task of science is not to differentiate the true from the false—it is to solve scientific problems. 
To say that someone did something because he is a madman is to confess that we cannot really explain it at all. This is the fundamental insight, and the methodological point, behind the rationality principle.
The rationality principle is not the empirical hypothesis that each person acts adequately to the situation. That hypothesis is clearly false. It is, on the contrary, a methodological principle that places restrictions on what will and will not count as a rational explanation. It says that if we want to explain a social event rationally, then we must assume that the people in it acted adequately to the situation, or, at the very least, that they acted adequately to the situation as they saw it. 
There is … an infinite number of true statements about the world that no empirical science would ever, or should ever, take notice [of]. 
Popper did not regard socialism or capitalism or any economic system as an end in itself. He thought that such systems are to be valued—and evaluated—primarily as means toward freedom. The same holds true for political systems. Even democracy should be valued as a means to another end. It may well help us to preserve freedom, but it can never create freedom if we ourselves do not care for it. 
If the purpose of an argument is to prove its conclusion, then it is difficult to see the point of falsifiability. For deductive arguments cannot prove their conclusions any more than inductive ones can.
But if the purpose of the argument is to force us to choose, then the point of falsifiability becomes clear.
Deductive arguments force us to question, and to reexamine, and, ultimately, to deny their premises if we want to deny their conclusions. Inductive arguments simply do not.
This the real meaning of Popper’s Logic of Scientific Discovery—and it is the reason, perhaps, why so many readers have misunderstood its title and its intent. The logic of discovery is not the logic of discovering theories, and it is not the logic of discovering that they are true.
Neither deduction nor induction can serve as a logic for that.
The logic of discovery is the logic of discovering our errors. We simply cannot deny the conclusion of a deductive argument without discovering that we were in error about its premises. Modus tollens can help us to do this if we use it to set problems for our theories. But while inductive arguments may persuade or induce us to believe things, they cannot help us discover that we are in error about their premises. [113-4]