Problems popper

The scientific method, as mentioned, involves observation and experimentation (research) to discover or establish facts. These are followed by deduction or hypothesis, establishing theories or principles. This sequence, however, may be reversed. The noted twentieth-century philosopher Karl Popper, who also dealt with science, expressed the view that the scientist s work starts not with collection of data (observation) but with selection of a suitable problem (theory). In fact, both of these paths can be involved. vSignificant and sometimes accidental observations can be made without any preconceived idea of a problem or theory and vice versa. The scientist, however, must have a well-prepared, open mind to be able to recognize the significance of such observations and must be able to follow them through. Science always demands rigorous standards of procedure, reproducibility, and open discussion that set reason over irrational belief. 

But what influence do psychological factors have on the working techniques of scientists Popper (1970) has doubts whether the regress to these often spurious sciences (i.e., psychology) can help us in the elucidation of these problems. ... 

A quotation from another great man of the 17th century refers to the same problem. Spinoza wrote in 1674 Omnis determinatio est negatio , i.e., each determination comes from a negation. If we take negatio as a description of falsification, we come to the basis of Popper s theory. Only a falsification is a real advance, because only this, but not a verification, is final. 

The short summary here of Popper s and Kuhn s contributions to the philosophy of science is based, in the case of Popper, only on his early work, which emphasized logic and classified psychology as not scientific. It should be emphasized that the later work of Popper, particularly in the last two decades, demonstrates his broad and deep ideas covering much more than the philosophy of science in a narrow sense. An excellent example is his opinion on precision, as published in Popper s autobiography (1982, p. 24) The quest for precision is analogous to the quest for certainty, and both should be abandoned. .. One should never try to be more precise than the problem demands. .. It is always undesirable to make an effort to increase precision for its own sake — especially linguistic precision — since this usually leads to loss of clarity. ... 

One potential solution to these problems, suggested some 20 years ago by Chantrell and Popper (1), involves the use of inorganic or organo-metallic polymers as precursors to the desired ceramic material. The concept (2) centers on the use of a tractable (soluble, meltable or malleable) inorganic precursor polymer that can be shaped at low temperature (as one shapes organic polymers) into a coating, a fiber or as a matrix (binder) for a ceramic powder. Once the final shape is obtained, the precursor polymer can be pyrolytically transformed into the desired ceramic material. With careful control of the pyrolysis conditions, the final piece will have the appropriate physical and/or electronic properties. 

As a simple illustration of the difference between t and r, consider two cases of the steady-flow popcorn popper of Problem 4.7 which takes in 1 liter/min of raw corn and produces 28 liters/min of product popcorn. 

In Science, Pseudo-Science and Falsifiability Popper tackles the problem of the strength of a theory. He remarked that the apparent strength of theories which can explain everything was in fact their weakness. The impressive thing about strong theories is the risk involved in their predictions The criterion of the scientitic status of a theory is its falsifiability, or refutability, or testability This places Testing in the middle of this discussion ... 

This is nothing more than a statement of the Problem of Induction in scientific research, and the interested reader is referred to Popper for a detailed discussion and analysis of such philosophical issues. 

Unfortunately, it is impossible to design an experiment that will totally disprove a theory based on random phenomena. Various outcomes may occur, some of which may be unlikely but not impossible. Thus Popper s falsifiability condition does not apply. The statistical method advocated by Fisher (1956) attempts to overcome this problem by substituting unlikely for impossible but otherwise follows the principles of the scientific method. With this substitution, Fisher and others proposed conceptual structures for testing theories and scientific hypotheses under conditions of uncertainty that are analogous to the scientific method. However, these approaches, although being very useful in practice, have raised a host of conceptual issues that are the subject of ongoing debates. 

One problem with any material with a layered structure is that these materials often exhibit stacking faults. As the structure is the same in two dimensions, it can easily be disrupted to produce the wrong stacking sequence. As the layer sequence becomes more complex, the hkeh-hood of stacking faults increases. Many Ruddlesden-Popper phases exist for = 1, but as n increases the number of known phases decreases. This is likely to be related to the increased formation of stacking faults, which prevents isolation of the perfectly ordered phase for characterization purposes. 

As we saw in Chapter 4, our food supply has become relatively mineral-deficient in recent decades, mostly because of agricultural practices. It could be that Popper s observations are reflecting the effects of subtle mineral deficiencies, which for some people have dramatic effects on mood. Or perhaps there is some sort of genetic metabolic problem that makes some people particularly vulnerable to mood disorders when they don t get enough minerals. Scientists are still trying to figure it out. 

Popper Karl (1968) Is there an epistemological problem of perception In Lakatos Imre, Musgrave Alan (eds.). Problems in the philosophy of science, North-Holland Publishing Company, Amsterdam, 1968 pp. 40-64. 

Quite simply. Popper rejected the old idea of inductive reasoning and replaced it with a completely new scheme based on problem solving, a scheme which, if true for science, makes scientific research and engineering design very similar indeed. In order to isolate the differences we shall have to pursue Popper s ideas further. 

This view of Popper is, of course, an evolutionary one. The principle activity is problem solving and the principle problem is survival. In animals, new reactions, new modes of behaviour and new expectations evolve from trial solutions to problems which are successful in overcoming those problems. The creature itself may be modified in one of its organs or in one of its forms. In humans one development is of importance above all others and that is the development of... 

The likelihood interpretation can, however, be intuitively unsatisfactory as Popper points out. Consider the following problem idealised to illustrate the point. A structure has 10 limit states (Z,i, Li,. . . Ljo) all judged to be equally likely to occur. We make a hypothesis h — the structure will fail in 4. Imagine the evidence turns out to be Ci — the structure failed in Z-4 or L5 or jLg. Then the likelihood function becomes LQijei) = P ei/h) - 1 which is unsatisfactory, but... 

Again Popper s ideas might be useful in such studies he argues that, In all social sciences we have individuals who do things who want things who have certain aims. In so far as they act in the way in which they want to act and realise the aims which they intend to realise, no problems arise for the social sciences (except the problem whether their wants and aims can perhaps be socially explained, for example by certain traditions). The characteristic problems of the social sciences arise only out of our wish to know the unintended consequences, and more especially, the unwanted consequences which may arise if we do certain things. We wish to foresee not only the direct consequences but also these unwanted indirect consequences. [6]... 

The central tenets of the falsificationist philosophy of Karl R. Popper are reviewed in detail, and the way they do or do not apply to systematics and phylogeny reconstruction is analyzed. Cladistic analysis, cast in either maximum parsimony or in maximum likelihood approaches, is not compatible with Popperian falsificationism. The main reasons are the absence of a deductive link between a hypothesis of phylogenetic relationships and character distribution on a tree, which translates into the absence of the basic asymmetry of falsification versus verification. This sets Popper s philosophy of science apart from inductive systems. In cladistic analysis, falsification (disconfirmation) is symmetrical to verification (confirmation), which reveals an inductive and hence probabilistic background. The basic problem of systematics as an empirical science resides in character conceptualization and its critical evaluation. 

Those two problems are, indeed, interdependent. Popper considered the issue of how science is done a matter of interpretation (Popper, 1976 80) the issue of how science should be done he deemed a matter of sociology (Popper, 1974a 1036). Yet Popper stressed repeatedly that a philosophy of science must take into account the way science is actually practiced (Popper 1979 134). Beyond the mere cultivation of a critical attitude, the question thus becomes whether the logic of systematics matches in any way the logic of scientific discovery as analyzed and formalized by Popper (1976). 

These formalisms therefore are supposed to work in principle as a matter of logic that governs the relations between scientific statements or complexes thereof, not as a matter of probability calculus (Popper, 1973 51 see also Appendix 11). In his later writings. Popper dealt extensively with probability arguments in order to deal with the problems that the developing insights in quantum physics caused for his solution to the problem of induction but his efforts in this direction always concerned physical effects in the form of reproducible regularities (Popper, 1976 68), not historical relationships. In a similar sense, the axiom of likelihood applies to statistical populations of data only, not to historical processes (Edwards, 1992). 

Popper took up the problem of induction where Hume had left it Are we justified in reasoning from [repeated] instances of which we have experience to other instances [conclusions] of which we have no experience (Popper, 1973 8), or, more simply put, what allows us to expect that the future will resemble the past Or yet simpler, is it possible to know more than we know ... 

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