Karl Popper (–) war als Verteidiger der demokratisch liberalen Gesellschaften des Westens gegen Ende des Jahrhunderts der. Popper waren die Mitglieder einer deutschen Jugendkultur in Westdeutschland, West-Berlin und der DDR der ersten Hälfte der er Jahre. In Österreich. Popper ist darauf immer wieder zu sprechen gekommen. So heißt es im Vorwort zur 3. deutschen Auflage der Logik der Forschung „ Der modische Kult.
Sir Karl Raimund. Sir Karl Raimund Popper CH FBA FRS war ein österreichisch-britischer Philosoph, der mit seinen Arbeiten zur Erkenntnis- und Wissenschaftstheorie, zur Sozial- und Geschichtsphilosophie sowie zur politischen Philosophie den kritischen Rationalismus. Popper waren die Mitglieder einer deutschen Jugendkultur in Westdeutschland, West-Berlin und der DDR der ersten Hälfte der er Jahre. In Österreich. Popper-Bewegung Aalglatt bis zum Anschlag. Karottenjeans und Kaschmirpulli: Unverhohlen trugen die Popper Anfang der Achtzigerjahre. Popper ist darauf immer wieder zu sprechen gekommen. So heißt es im Vorwort zur 3. deutschen Auflage der Logik der Forschung „ Der modische Kult. Geburtstag von Karl R. Popper Kurt Salamun. Franz M. Wuketits EVOLUTIONÄRE ERKENNTNISTHEORIE, POPPERS “ DREI - WELTEN - LEHRE ” UND DAS. Neukantianische Anfänge Was Poppers Denken von Anfang an charakterisiert, das ist die große Nähe zu den Arbeiten des „ Wiener Kreises “ bei gleichzeitiger.
Simon Siegmund Carl Popper und dessen Frau Jenny (geb. Schiff) in Wien geboren. Popper verlässt vorzeitig die Schule und belegt an der Universität. Poppers Hauptwerk "Die offene Gesellschaft und ihre Feinde" erschien , ist jetzt wieder hochaktuell. Popper unterscheidet "offene". Popper ist darauf immer wieder zu sprechen gekommen. So heißt es im Vorwort zur 3. deutschen Auflage der Logik der Forschung „ Der modische Kult. Hier wird seit sein Gesellenbrief und ein Nachbau seines Gesellenstücks ausgestellt; das originale Wandkästchen steht in Poppers Haus in London. Im folgenden Jahr tritt Popper in regen Austausch mit dem "Wiener Kreis" um Moritz SchlickNein Danke Carnap und Otto Neurathin deren Zirkel vor allem erkenntnistheoretische und logische Probleme diskutiert werden. Popper schlägt stattdessen vor, dass Theorien abstrakt betrachtet frei erfunden werden dürfen. Vor einem Vierteljahrhundert, Popper Pfeil nach rechts. Namensräume Artikel Diskussion. The Philosophy of Karl Popper.
Popper held that it is the least likely, or most easily falsifiable, or simplest theory attributes which he identified as all the same thing that explains known facts that one should rationally prefer.
His opposition to positivism, which held that it is the theory most likely to be true that one should prefer, here becomes very apparent.
It is impossible, Popper argues, to ensure a theory to be true; it is more important that its falsity can be detected as easily as possible.
Popper agreed with David Hume that there is often a psychological belief that the sun will rise tomorrow and that there is no logical justification for the supposition that it will, simply because it always has in the past.
Popper writes,. I approached the problem of induction through Hume. Hume, I felt, was perfectly right in pointing out that induction cannot be logically justified.
Popper held that rationality is not restricted to the realm of empirical or scientific theories, but that it is merely a special case of the general method of criticism, the method of finding and eliminating contradictions in knowledge without ad-hoc measures.
According to this view, rational discussion about metaphysical ideas, about moral values and even about purposes is possible.
Popper's student W. Bartley III tried to radicalise this idea and made the controversial claim that not only can criticism go beyond empirical knowledge, but that everything can be rationally criticised.
To Popper, who was an anti- justificationist , traditional philosophy is misled by the false principle of sufficient reason. He thinks that no assumption can ever be or needs ever to be justified, so a lack of justification is not a justification for doubt.
Instead, theories should be tested and scrutinised. It is not the goal to bless theories with claims of certainty or justification, but to eliminate errors in them.
He writes,. The Philosophy of Karl Popper , p. Popper's principle of falsifiability runs into prima facie difficulties when the epistemological status of mathematics is considered.
If they are not open to falsification they can not be scientific. If they are not scientific, it needs to be explained how they can be informative about real world objects and events.
Popper's solution  was an original contribution in the philosophy of mathematics. In one sense it is irrefutable and logically true , in the second sense it is factually true and falsifiable.
Popper considered historicism to be the theory that history develops inexorably and necessarily according to knowable general laws towards a determinate end.
He argued that this view is the principal theoretical presupposition underpinning most forms of authoritarianism and totalitarianism.
He argued that historicism is founded upon mistaken assumptions regarding the nature of scientific law and prediction.
Since the growth of human knowledge is a causal factor in the evolution of human history, and since "no society can predict, scientifically, its own future states of knowledge",  it follows, he argued, that there can be no predictive science of human history.
For Popper, metaphysical and historical indeterminism go hand in hand. In his early years Popper was impressed by Marxism, whether of Communists or socialists.
An event that happened in had a profound effect on him: During a riot, caused by the Communists, the police shot several unarmed people, including some of Popper's friends, when they tried to free party comrades from prison.
However, he knew that the riot instigators were swayed by the Marxist doctrine that class struggle would produce vastly more dead men than the inevitable revolution brought about as quickly as possible, and so had no scruples to put the life of the rioters at risk to achieve their selfish goal of becoming the future leaders of the working class.
This was the start of his later criticism of historicism. In , Popper co-founded the Mont Pelerin Society , with Friedrich Hayek , Milton Friedman , Ludwig von Mises and others, although he did not fully agree with the think tank's charter and ideology.
Specifically, he unsuccessfully recommended that socialists should be invited to participate, and that emphasis should be put on a hierarchy of humanitarian values rather than advocacy of a free market as envisioned by classical liberalism.
Although Popper was an advocate of toleration, he also warned against unlimited tolerance. Unlimited tolerance must lead to the disappearance of tolerance.
If we extend unlimited tolerance even to those who are intolerant, if we are not prepared to defend a tolerant society against the onslaught of the intolerant, then the tolerant will be destroyed, and tolerance with them.
In this formulation, I do not imply, for instance, that we should always suppress the utterance of intolerant philosophies; as long as we can counter them by rational argument and keep them in check by public opinion, suppression would certainly be most unwise.
But we should claim the right to suppress them if necessary even by force; for it may easily turn out that they are not prepared to meet us on the level of rational argument, but begin by denouncing all argument; they may forbid their followers to listen to rational argument, because it is deceptive, and teach them to answer arguments by the use of their fists or pistols.
We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant. We should claim that any movement preaching intolerance places itself outside the law, and we should consider incitement to intolerance and persecution as criminal, in the same way as we should consider incitement to murder, or to kidnapping, or to the revival of the slave trade, as criminal.
Popper criticized what he termed the "conspiracy theory of society," the view that powerful people or groups, godlike in their efficacy, are responsible for purposely bringing about all the ills of society.
This view cannot be right, Popper argued, because "nothing ever comes off exactly as intended. As early as , Popper wrote of the search for truth as "one of the strongest motives for scientific discovery.
Then came the semantic theory of truth formulated by the logician Alfred Tarski and published in Popper wrote of learning in of the consequences of Tarski's theory, to his intense joy.
The theory met critical objections to truth as correspondence and thereby rehabilitated it. The theory also seemed, in Popper's eyes, to support metaphysical realism and the regulative idea of a search for truth.
According to this theory, the conditions for the truth of a sentence as well as the sentences themselves are part of a metalanguage. So, for example, the sentence "Snow is white" is true if and only if snow is white.
Although many philosophers have interpreted, and continue to interpret, Tarski's theory as a deflationary theory , Popper refers to it as a theory in which "is true" is replaced with " corresponds to the facts ".
He bases this interpretation on the fact that examples such as the one described above refer to two things: assertions and the facts to which they refer.
He identifies Tarski's formulation of the truth conditions of sentences as the introduction of a "metalinguistic predicate" and distinguishes the following cases:.
The first case belongs to the metalanguage whereas the second is more likely to belong to the object language. Hence, "it is true that" possesses the logical status of a redundancy.
Upon this basis, along with that of the logical content of assertions where logical content is inversely proportional to probability , Popper went on to develop his important notion of verisimilitude or "truthlikeness".
The intuitive idea behind verisimilitude is that the assertions or hypotheses of scientific theories can be objectively measured with respect to the amount of truth and falsity that they imply.
And, in this way, one theory can be evaluated as more or less true than another on a quantitative basis which, Popper emphasises forcefully, has nothing to do with "subjective probabilities" or other merely "epistemic" considerations.
The simplest mathematical formulation that Popper gives of this concept can be found in the tenth chapter of Conjectures and Refutations. Here he defines it as:.
Popper's original attempt to define not just verisimilitude, but an actual measure of it, turned out to be inadequate.
However, it inspired a wealth of new attempts. Knowledge, for Popper, was objective, both in the sense that it is objectively true or truthlike , and also in the sense that knowledge has an ontological status i.
He proposed three worlds :  World One, being the physical world, or physical states; World Two, being the world of mind, or mental states, ideas and perceptions; and World Three, being the body of human knowledge expressed in its manifold forms, or the products of the Second World made manifest in the materials of the First World i.
World Three, he argued, was the product of individual human beings in exactly the same sense that an animal's path is the product of individual animals, and thus has an existence and is evolution independent of any individually known subjects.
The influence of World Three, in his view, on the individual human mind World Two is at least as strong as the influence of World One.
In other words, the knowledge held by a given individual mind owes at least as much to the total, accumulated, wealth of human knowledge made manifest, comparably to the world of direct experience.
As such, the growth of human knowledge could be said to be a function of the independent evolution of World Three.
Many contemporary philosophers, such as Daniel Dennett, have not embraced Popper's Three World conjecture, mostly due to its resemblance to mind—body dualism.
The creation—evolution controversy in the United States raises the issue of whether creationistic ideas may be legitimately called science and whether evolution itself may be legitimately called science.
In the debate, both sides and even courts in their decisions have frequently invoked Popper's criterion of falsifiability see Daubert standard.
In this context, passages written by Popper are frequently quoted in which he speaks about such issues himself. For example, he famously stated " Darwinism is not a testable scientific theory, but a metaphysical research program—a possible framework for testable scientific theories.
And yet, the theory is invaluable. I do not see how, without it, our knowledge could have grown as it has done since Darwin.
In trying to explain experiments with bacteria which become adapted to, say, penicillin , it is quite clear that we are greatly helped by the theory of natural selection.
Although it is metaphysical, it sheds much light upon very concrete and very practical researches.
It allows us to study adaptation to a new environment such as a penicillin-infested environment in a rational way: it suggests the existence of a mechanism of adaptation, and it allows us even to study in detail the mechanism at work.
He also noted that theism , presented as explaining adaptation, "was worse than an open admission of failure, for it created the impression that an ultimate explanation had been reached".
When speaking here of Darwinism, I shall speak always of today's theory—that is Darwin's own theory of natural selection supported by the Mendelian theory of heredity , by the theory of the mutation and recombination of genes in a gene pool, and by the decoded genetic code.
This is an immensely impressive and powerful theory. The claim that it completely explains evolution is of course a bold claim, and very far from being established.
All scientific theories are conjectures, even those that have successfully passed many severe and varied tests. The Mendelian underpinning of modern Darwinism has been well tested, and so has the theory of evolution which says that all terrestrial life has evolved from a few primitive unicellular organisms, possibly even from one single organism.
In , regarding DNA and the origin of life he said:. What makes the origin of life and of the genetic code a disturbing riddle is this: the genetic code is without any biological function unless it is translated; that is, unless it leads to the synthesis of the proteins whose structure is laid down by the code.
But, as Monod points out, the machinery by which the cell at least the non-primitive cell, which is the only one we know translates the code "consists of at least fifty macromolecular components which are themselves coded in the DNA ".
Monod, ;  , . Thus the code can not be translated except by using certain products of its translation.
This constitutes a really baffling circle; a vicious circle, it seems, for any attempt to form a model, or theory, of the genesis of the genetic code.
Thus we may be faced with the possibility that the origin of life like the origin of the universe becomes an impenetrable barrier to science, and a residue to all attempts to reduce biology to chemistry and physics.
He explained that the difficulty of testing had led some people to describe natural selection as a tautology , and that he too had in the past described the theory as "almost tautological", and had tried to explain how the theory could be untestable as is a tautology and yet of great scientific interest:.
My solution was that the doctrine of natural selection is a most successful metaphysical research programme.
It raises detailed problems in many fields, and it tells us what we would expect of an acceptable solution of these problems.
I still believe that natural selection works in this way as a research programme. Nevertheless, I have changed my mind about the testability and logical status of the theory of natural selection; and I am glad to have an opportunity to make a recantation.
The theory of natural selection may be so formulated that it is far from tautological. In this case it is not only testable, but it turns out to be not strictly universally true.
There seem to be exceptions, as with so many biological theories; and considering the random character of the variations on which natural selection operates, the occurrence of exceptions is not surprising.
Thus not all phenomena of evolution are explained by natural selection alone. Yet in every particular case it is a challenging research program to show how far natural selection can possibly be held responsible for the evolution of a particular organ or behavioural program.
These frequently quoted passages are only a very small part of what Popper wrote on the issue of evolution, however, and give the wrong impression that he mainly discussed questions of its falsifiability.
Popper never invented this criterion to give justifiable use of words like science. In fact, Popper stresses at the beginning of Logic of Scientific Discovery that "the last thing I wish to do, however, is to advocate another dogma"  and that "what is to be called a 'science' and who is to be called a 'scientist' must always remain a matter of convention or decision.
I do not try to justify [the aims of science which I have in mind], however, by representing them as the true or the essential aims of science.
This would only distort the issue, and it would mean a relapse into positivist dogmatism. There is only one way, as far as I can see, of arguing rationally in support of my proposals.
This is to analyse their logical consequences: to point out their fertility—their power to elucidate the problems of the theory of knowledge.
Popper had his own sophisticated views on evolution  that go much beyond what the frequently-quoted passages say. Popper understood the universe as a creative entity that invents new things, including life, but without the necessity of something like a god, especially not one who is pulling strings from behind the curtain.
He said that evolution of the genotype must, as the creationists say, work in a goal-directed way  but disagreed with their view that it must necessarily be the hand of god that imposes these goals onto the stage of life.
Instead, he formulated the spearhead model of evolution , a version of genetic pluralism. According to this model, living organisms themselves have goals, and act according to these goals, each guided by a central control.
In its most sophisticated form, this is the brain of humans, but controls also exist in much less sophisticated ways for species of lower complexity, such as the amoeba.
This control organ plays a special role in evolution—it is the "spearhead of evolution". The goals bring the purpose into the world.
Mutations in the genes that determine the structure of the control may then cause drastic changes in behaviour, preferences and goals, without having an impact on the organism's phenotype.
Popper postulates that such purely behavioural changes are less likely to be lethal for the organism compared to drastic changes of the phenotype.
Popper contrasts his views with the notion of the "hopeful monster" that has large phenotype mutations and calls it the "hopeful behavioural monster".
After behaviour has changed radically, small but quick changes of the phenotype follow to make the organism fitter to its changed goals.
This way it looks as if the phenotype were changing guided by some invisible hand, while it is merely natural selection working in combination with the new behaviour.
For example, according to this hypothesis, the eating habits of the giraffe must have changed before its elongated neck evolved.
Popper contrasted this view as "evolution from within" or "active Darwinism" the organism actively trying to discover new ways of life and being on a quest for conquering new ecological niches ,   with the naturalistic "evolution from without" which has the picture of a hostile environment only trying to kill the mostly passive organism, or perhaps segregate some of its groups.
Popper was a key figure encouraging patent lawyer Günter Wächtershäuser to publish his iron—sulfur world hypothesis on abiogenesis and his criticism of "soup" theory.
Raven when, in his Science, Religion, and the Future , , he calls this conflict 'a storm in a Victorian tea-cup'; though the force of this remark is perhaps a little impaired by the attention he pays to the vapours still emerging from the cup—to the Great Systems of Evolutionist Philosophy, produced by Bergson, Whitehead, Smuts, and others.
In his later work, however, when he had developed his own "spearhead model" and "active Darwinism" theories, Popper revised this view and found some validity in the controversy:.
I have to confess that this cup of tea has become, after all, my cup of tea; and with it I have to eat humble pie.
Popper and John Eccles speculated on the problem of free will for many years, generally agreeing on an interactionist dualist theory of mind.
However, although Popper was a body-mind dualist, he did not think that the mind is a substance separate from the body : he thought that mental or psychological properties or aspects of people are distinct from physical ones.
When he gave the second Arthur Holly Compton Memorial Lecture in , Popper revisited the idea of quantum indeterminacy as a source of human freedom.
Eccles had suggested that "critically poised neurons" might be influenced by the mind to assist in a decision. Popper criticised Compton's idea of amplified quantum events affecting the decision.
He wrote:. The idea that the only alternative to determinism is just sheer chance was taken over by Schlick , together with many of his views on the subject, from Hume , who asserted that "the removal" of what he called "physical necessity" must always result in "the same thing with chance.
As objects must either be conjoin'd or not, I shall later argue against this important doctrine according to which the alternative to determinism is sheer chance.
Yet I must admit that the doctrine seems to hold good for the quantum-theoretical models which have been designed to explain, or at least to illustrate, the possibility of human freedom.
This seems to be the reason why these models are so very unsatisfactory. Hume's and Schlick's ontological thesis that there cannot exist anything intermediate between chance and determinism seems to me not only highly dogmatic not to say doctrinaire but clearly absurd; and it is understandable only on the assumption that they believed in a complete determinism in which chance has no status except as a symptom of our ignorance.
Popper called not for something between chance and necessity but for a combination of randomness and control to explain freedom, though not yet explicitly in two stages with random chance before the controlled decision, saying, "freedom is not just chance but, rather, the result of a subtle interplay between something almost random or haphazard, and something like a restrictive or selective control.
Then in his book with John Eccles, The Self and its Brain , Popper finally formulates the two-stage model in a temporal sequence.
And he compares free will to Darwinian evolution and natural selection:. New ideas have a striking similarity to genetic mutations.
Now, let us look for a moment at genetic mutations. Mutations are, it seems, brought about by quantum theoretical indeterminacy including radiation effects.
Accordingly, they are also probabilistic and not in themselves originally selected or adequate, but on them there subsequently operates natural selection which eliminates inappropriate mutations.
Now we could conceive of a similar process with respect to new ideas and to free-will decisions, and similar things. That is to say, a range of possibilities is brought about by a probabilistic and quantum mechanically characterised set of proposals, as it were—of possibilities brought forward by the brain.
On these there then operates a kind of selective procedure which eliminates those proposals and those possibilities which are not acceptable to the mind.
In an interview  that Popper gave in with the condition that it should be kept secret until after his death, he summarised his position on God as follows: "I don't know whether God exists or not.
Some forms of atheism are arrogant and ignorant and should be rejected, but agnosticism —to admit that we don't know and to search—is all right.
When I look at what I call the gift of life, I feel a gratitude which is in tune with some religious ideas of God. However, the moment I even speak of it, I am embarrassed that I may do something wrong to God in talking about God.
Why then should the Jewish myth be true and the Indian and Egyptian myths not be true? Popper helped to establish the philosophy of science as an autonomous discipline within philosophy, through his own prolific and influential works, and also through his influence on his own contemporaries and students.
Popper founded in the Department of Philosophy, Logic and Scientific Method at the London School of Economics and there lectured and influenced both Imre Lakatos and Paul Feyerabend , two of the foremost philosophers of science in the next generation of philosophy of science.
Lakatos significantly modified Popper's position,  : 1 and Feyerabend repudiated it entirely, but the work of both is deeply influenced by Popper and engaged with many of the problems that Popper set.
While there is some dispute as to the matter of influence, Popper had a long-standing and close friendship with economist Friedrich Hayek , who was also brought to the London School of Economics from Vienna.
Each found support and similarities in the other's work, citing each other often, though not without qualification.
In a letter to Hayek in , Popper stated, "I think I have learnt more from you than from any other living thinker, except perhaps Alfred Tarski.
For his part, Hayek dedicated a collection of papers, Studies in Philosophy, Politics, and Economics , to Popper, and in said, " Popper also had long and mutually influential friendships with art historian Ernst Gombrich , biologist Peter Medawar , and neuroscientist John Carew Eccles.
The German jurist Reinhold Zippelius uses Popper's method of "trial and error" in his legal philosophy. Popper's influence, both through his work in philosophy of science and through his political philosophy, has also extended beyond the academy.
Most criticisms of Popper's philosophy are of the falsification , or error elimination, element in his account of problem solving. Popper presents falsifiability as both an ideal and as an important principle in a practical method of effective human problem solving; as such, the current conclusions of science are stronger than pseudo-sciences or non-sciences , insofar as they have survived this particularly vigorous selection method.
He does not argue that any such conclusions are therefore true, or that this describes the actual methods of any particular scientist.
Rather, it is recommended as an essential principle of methodology that, if enacted by a system or community, will lead to slow but steady progress of a sort relative to how well the system or community enacts the method.
It has been suggested that Popper's ideas are often mistaken for a hard logical account of truth because of the historical co-incidence of their appearing at the same time as logical positivism , the followers of which mistook his aims for their own.
The Quine—Duhem thesis argues that it is impossible to test a single hypothesis on its own, since each one comes as part of an environment of theories.
Thus we can only say that the whole package of relevant theories has been collectively falsified , but cannot conclusively say which element of the package must be replaced.
An example of this is given by the discovery of the planet Neptune : when the motion of Uranus was found not to match the predictions of Newton's laws , the theory "There are seven planets in the solar system" was rejected, and not Newton's laws themselves.
Popper discussed this critique of naive falsificationism in Chapters 3 and 4 of The Logic of Scientific Discovery. The philosopher Thomas Kuhn writes in The Structure of Scientific Revolutions that he places an emphasis on anomalous experiences similar to that Popper places on falsification.
However, he adds that anomalous experiences cannot be identified with falsification, and questions whether theories could be falsified in the manner suggested by Popper.
Popper claimed to have recognised already in the version of his Logic of Discovery a fact later stressed by Kuhn, "that scientists necessarily develop their ideas within a definite theoretical framework", and to that extent to have anticipated Kuhn's central point about "normal science".
Science must begin with myths, and with the criticism of myths; neither with the collection of observations, nor with the invention of experiments, but with the critical discussion of myths, and of magical techniques and practices.
The scientific tradition is distinguished from the pre-scientific tradition in having two layers. Like the latter, it passes on its theories; but it also passes on a critical attitude towards them.
The theories are passed on, not as dogmas, but rather with the challenge to discuss them and improve upon them.
Another objection is that it is not always possible to demonstrate falsehood definitively, especially if one is using statistical criteria to evaluate a null hypothesis.
More generally it is not always clear, if evidence contradicts a hypothesis, that this is a sign of flaws in the hypothesis rather than of flaws in the evidence.
However, this is a misunderstanding of what Popper's philosophy of science sets out to do. Rather than offering a set of instructions that merely need to be followed diligently to achieve science, Popper makes it clear in The Logic of Scientific Discovery that his belief is that the resolution of conflicts between hypotheses and observations can only be a matter of the collective judgment of scientists, in each individual case.
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The kind of reasoning which has made, and continues to make, historicism plausible may, on this account, be reconstructed as follows: if the application of the laws of the natural sciences can lead to the successful prediction of such future events as eclipses, then surely it is reasonable to infer that knowledge of the laws of history as yielded by a social science or sciences assuming that such laws exist would lead to the successful prediction of such future social phenomena as revolutions?
Why should it be possible to predict an eclipse, but not a revolution? Why can we not conceive of a social science which could and would function as the theoretical natural sciences function, and yield precise unconditional predictions in the appropriate sphere of application?
These are amongst the questions which Popper seeks to answer, and in doing so, to show that they are based upon a series of misconceptions about the nature of science, and about the relationship between scientific laws and scientific prediction.
Contrary to popular belief, it is the former rather than the latter which are typical of the natural sciences, which means that typically prediction in natural science is conditional and limited in scope—it takes the form of hypothetical assertions stating that certain specified changes will come about if particular specified events antecedently take place.
However, Popper argues that a these unconditional prophecies are not characteristic of the natural sciences, and b that the mechanism whereby they occur, in the very limited way in which they do, is not understood by the historicist.
What is the mechanism which makes unconditional scientific prophecies possible? The answer is that such prophecies can sometimes be derived from a combination of conditional predictions themselves derived from scientific laws and existential statements specifying that the conditions in relation to the system being investigated are fulfilled.
Schematically, this can be represented as follows:. The most common examples of unconditional scientific prophecies in science relate to the prediction of such phenomena as lunar and solar eclipses and comets.
Given, then, that this is the mechanism which generates unconditional scientific prophecies, Popper makes two related claims about historicism: a That the historicist does not in fact derive his unconditional scientific prophecies in this manner from conditional predictions, and b the historicist cannot do so because long-term unconditional scientific prophecies can be derived from conditional predictions only if they apply to systems which are well-isolated, stationary, and recurrent like our solar system.
Such systems are quite rare in nature, and human society is most emphatically not one of them. This, then, Popper argues, is the reason why it is a fundamental mistake for the historicist to take the unconditional scientific prophecies of eclipses as being typical and characteristic of the predictions of natural science—in fact such predictions are possible only because our solar system is a stationary and repetitive system which is isolated from other such systems by immense expanses of empty space.
The solar system aside, there are very few such systems around for scientific investigation—most of the others are confined to the field of biology, where unconditional prophecies about the life-cycles of organisms are made possible by the existence of precisely the same factors.
Thus one of the fallacies committed by the historicist is to take the relatively rare instances of unconditional prophecies in the natural science as constituting the essence of what scientific prediction is, to fail to see that such prophecies apply only to systems which are isolated, stationary, and repetitive, and to seek to apply the method of scientific prophecy to human society and human history.
In the most fundamental sense possible, every event in human history is discrete, novel, quite unique, and ontologically distinct from every other historical event.
For this reason, it is impossible in principle that unconditional scientific prophecies could be made in relation to human history—the idea that the successful unconditional prediction of eclipses provides us with reasonable grounds for the hope of successful unconditional prediction regarding the evolution of human history turns out to be based upon a gross misconception, and is quite false.
This argument is one of the strongest that has ever been brought against historicism, cutting, as it does, right to the heart of one of its main theoretical presuppositions.
An additional mistake which he detects in historicism is the failure of the historicist to distinguish between scientific laws and trends , which is also frequently accompanied by a simple logical fallacy.
The fallacy is that of inferring from the fact that our understanding of any past historical event—such as, for example, the French Revolution—is in direct proportion to our knowledge of the antecedent conditions which led to that event, that knowledge of all the antecedent conditions of some future event is possible, and that such knowledge would make that future event precisely predictable.
For the truth is that the number of factors which predate and lead to the occurrence of any event, past, present, or future, is indefinitely large, and therefore knowledge of all of these factors is impossible, even in principle.
This failure makes him think it possible to explain change by discovering trends running through past history, and to anticipate and predict future occurrences on the basis of such observations.
Here Popper points out that there is a critical difference between a trend and a scientific law, the failure to observe which is fatal.
For a scientific law is universal in form, while a trend can be expressed only as a singular existential statement. This logical difference is crucial because unconditional predictions, as we have already seen, can be based only upon conditional ones, which themselves must be derived from scientific laws.
Neither conditional nor unconditional predictions can be based upon trends, because these may change or be reversed with a change in the conditions which gave rise to them in the first instance.
Popper does not, of course, dispute the existence of trends, nor does he deny that the observation of trends can be of practical utility value—but the essential point is that a trend is something which itself ultimately stands in need of scientific explanation, and it cannot therefore function as the frame of reference in terms of which anything else can be scientifically explained or predicted.
A point which connects with this has to do with the role which the evolution of human knowledge has played in the historical development of human society.
It is incontestable that, as Marx himself observed, there has been a causal link between the two, in the sense that advances in scientific and technological knowledge have given rise to widespread global changes in patterns of human social organisation and social interaction, which in turn have led to social structures e.
In short, the evolution of human history has been strongly influenced by the growth of human knowledge , and it is extremely likely that this will continue to be the case—all the empirical evidence suggests that the link between the two is progressively consolidating.
However, this gives rise to further problems for the historicist. Moreover, he argues, it is logically demonstrable by a consideration of the implications of the fact that no scientific predictor, human or otherwise, can possibly predict, by scientific methods, its own future results.
The Poverty of Historicism , vii. Thus, while the future evolution of human history is extremely likely to be influenced by new developments in human knowledge, as it always has in the past, we cannot now scientifically determine what such knowledge will be.
From this it follows that if the future holds any new discoveries or any new developments in the growth of our knowledge and given the fallible nature of the latter, it is inconceivable that it does not , then it is impossible for us to predict them now, and it is therefore impossible for us to predict the future development of human history now, given that the latter will, at least in part, be determined by the future growth of our knowledge.
Thus once again historicism collapses—the dream of a theoretical, predictive science of history is unrealisable, because it is an impossible dream.
Accordingly, recognition that there are no such laws, and that unconditional predictions about future history are based, at best, upon nothing more substantial than the observation of contingent trends, shows that, from a purely theoretical as well as a practical point of view, large-scale social planning is indeed a recipe for disaster.
In summary, unconditional large-scale planning for the future is theoretically as well as practically misguided, because, again, part of what we are planning for is our future knowledge, and our future knowledge is not something which we can in principle now possess—we cannot adequately plan for unexpected advances in our future knowledge, or for the effects which such advances will have upon society as a whole.
The acceptance of historical indeterminism, then, as the only philosophy of history which is commensurate with a proper understanding of the nature of scientific knowledge, fatally undermines both historicism and holism.
This part of his social philosophy was influenced by the economist Friedrich Hayek, who worked with him at the London School of Economics and who was a life-long friend.
This, of course, parallels precisely the critical testing of theories in scientific investigation. For this reason, in a genuinely open society piecemeal social engineering goes hand-in-hand for Popper with negative utilitarianism the attempt to minimise the amount of misery, rather than, as with positive utilitarianism, the attempt to maximise the amount of happiness.
The state, he holds, should concern itself with the task of progressively formulating and implementing policies designed to deal with the social problems which actually confront it, with the goal of eliminating human misery and suffering to the highest possible degree.
The positive task of increasing social and personal happiness, by contrast, can and should be left to individual citizens who may, of course, act collectively to this end , who, unlike the state, have at least a chance of achieving this goal, but who in a free society are rarely in a position to systematically subvert the rights of others in the pursuit of idealised objectives.
Thus in the final analysis for Popper the activity of problem-solving is as definitive of our humanity at the level of social and political organisation as it is at the level of science, and it is this key insight which unifies and integrates the broad spectrum of his thought.
While it cannot be said that Popper was a modest man, he took criticism of his theories very seriously, and spent much of his time in his later years trying to show that such criticisms were either based upon misunderstandings, or that his theories could, without loss of integrity, be made compatible with new and important insights.
The following is a summary of some of the main criticisms which he has had to address. Schilpp ed. Bartley III.
Rather they are descriptions of what is observed as interpreted by the observer with reference to a determinate theoretical framework.
He accordingly asserts that basic statements themselves are open-ended hypotheses: they have a certain causal relationship with experience, but they are not determined by experience, and they cannot be verified or confirmed by experience.
But how can this be known, if such basic statements cannot be verified by experience? Logic of Scientific Discovery , Popper himself is fond of citing, as an example of such a critical test, the resolution, by Adams and Leverrier, of the problem which the anomalous orbit of Uranus posed for nineteenth century astronomers.
Both men independently came to the conclusion that, assuming Newtonian mechanics to be precisely correct, the observed divergence in the elliptical orbit of Uranus could be explained if the existence of a seventh, as yet unobserved outer planet was posited.
Yet Lakatos flatly denies that there are critical tests, in the Popperian sense, in science, and argues the point convincingly by turning the above example of an alleged critical test on its head.
What, he asks, would have happened if Galle had not found the planet Neptune? Such theories are, it is now generally accepted, highly resistant to falsification.
They are falsified, if at all, Lakatos argues, not by Popperian critical tests, but rather within the elaborate context of the research programmes associated with them gradually grinding to a halt, with the result that an ever-widening gap opens up between the facts to be explained, and the research programmes themselves Lakatos , passim.
The existence of such anomalies is not usually taken by the working scientist as an indication that the theory in question is false; on the contrary, he will usually, and necessarily, assume that the auxiliary hypotheses which are associated with the theory can be modified to incorporate, and explain, existing anomalies.
Scientific laws are expressed by universal statements i. In themselves they are not existential in nature. Since scientific laws are non-existential in nature, they logically cannot imply any basic statements, since the latter are explicitly existential.
The question arises, then, as to how any basic statement can falsify a scientific law, given that basic statements are not deducible from scientific laws in themselves?
This reply is adequate only if it is true, as Popper assumes, that singular existential statements will always do the work of bridging the gap between a universal theory and a prediction.
The working scientist, Putnam argues, always initially assumes that it is the latter, which shows not only that scientific laws are, contra Popper, highly resistant to falsification, but also why they are so highly resistant to falsification.
Hence his final concern is to outline conditions which indicate when such modification is genuinely scientific, and when it is merely ad hoc.
It is now condemned as unscientific by Popper because the only rationale for the modifications which were made to the original theory was to ensure that it evaded falsification, and so such modifications were ad hoc , rather than scientific.
This contention—though not at all implausible—has, to hostile eyes, a somewhat contrived air about it, and is unlikely to worry the convinced Marxist.
Life 2. Backdrop to his Thought 3. The Problem of Demarcation 4. The Growth of Human Knowledge 5. Probability, Knowledge and Verisimilitude 6.
Scientific Knowledge, History, and Prediction 8. Immutable Laws and Contingent Trends 9. Life Karl Raimund Popper was born on 28 July in Vienna, which at that time could make some claim to be the cultural epicentre of the western world.
The Problem of Demarcation As Popper represents it, the central problem in the philosophy of science is that of demarcation, i. The Growth of Human Knowledge For Popper accordingly, the growth of human knowledge proceeds from our problems and from our attempts to solve them.
Probability, Knowledge and Verisimilitude In the view of many social scientists, the more probable a theory is, the better it is, and if we have to choose between two theories which are equally strong in terms of their explanatory power, and differ only in that one is probable and the other is improbable, then we should choose the former.
In this connection, Popper had written: Ultimately, the idea of verisimilitude is most important in cases where we know that we have to work with theories which are at best approximations—that is to say, theories of which we know that they cannot be true.
This is often the case in the social sciences. In these cases we can still speak of better or worse approximations to the truth and we therefore do not need to interpret these cases in an instrumentalist sense.
Immutable Laws and Contingent Trends This argument is one of the strongest that has ever been brought against historicism, cutting, as it does, right to the heart of one of its main theoretical presuppositions.
Critical Evaluation While it cannot be said that Popper was a modest man, he took criticism of his theories very seriously, and spent much of his time in his later years trying to show that such criticisms were either based upon misunderstandings, or that his theories could, without loss of integrity, be made compatible with new and important insights.
Dissertation, University of Vienna, unpublished, The Poverty of Historicism 2nd edition, London: Routledge, Eccles, London: Springer International, Bartley III ed.
Realism and the Aim of Science , W. Notturno ed.Diesen Indeterminismus übertrug er auch auf gesellschaftliche Zustände Die Zukunft ist offen. September ; abgerufen am Popper bildeten keine exklusive Cars Ganzer Film Deutsch, sondern formten mehr Popper weniger lose Cliquen. Popper - nur ein Stil, der längst vergangen ist? Jedoch distanzierte er sich schon in der Logik der Forschung entschieden von der positivistischen Position, dass derartige Fragen überhaupt nicht sinnvoll formulierbar Popper, und wies Rice Kiste entsprechenden Versuche zurück, ein empiristisches Sinnkriterium zu formulieren. Icon: Der Spiegel. Die geistesgeschichtlichen Wurzeln des letzteren sieht er vor allem in einer Kombination hegelianischer Geschichtsphilosophie mit den neomalthusianischen Biologismen des späten NZZ Geschichte. Seine Eltern waren zum Protestantismus konvertierte assimilierte Juden. In: Popper Letters6, Tschick Film Online Schauen, S.