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365/365 – Moore’s Paradox

August 29, 2012 Leave a comment

Moore’s paradox concerns the putative absurdity involved in asserting a first-person present-tense sentence such as ‘It’s raining but I don’t believe that it is raining’ or ‘It’s raining but I believe that it is not raining’.

The first author to note this apparent absurdity was G.E. Moore. These ‘Moorean’ sentences, as they have become known:

 1.can be true,

 2.are (logically) consistent, and moreover

 3.are not (obviously) contradictions.

The ‘paradox’ consists in explaining why asserting a Moorean sentence is (or less strongly, strikes us as being) weird, absurd or nonsensical in some way.

The term ‘Moore’s Paradox’ is due to Ludwig Wittgenstein, who considered it Moore’s most important contribution to philosophy.

Wittgenstein devoted numerous remarks to the problem in his later writings, which has brought Moore’s Paradox the attention it might otherwise not have received.

Subsequent commentators have further noted that there is an apparent residual absurdity in asserting a first-person future-tense sentence such as ‘It will be raining and I will believe that it is not raining’.

Moore’s Paradox has also been connected to many other of the well-known logical paradoxes including, though not limited to, the liar paradox, the knower paradox, the unexpected hanging paradox, and the Preface paradox.

There is currently no generally accepted explanation of Moore’s Paradox in the philosophical literature.

However, while Moore’s Paradox has perhaps been seen as a philosophical curiosity by philosophers themselves, Moorean-type sentences are used by logicians, computer scientists, and those working in the artificial intelligence community, as examples of cases in which a knowledge, belief or information system is unsuccessful in updating its knowledge/belief/information store in the light of new or novel information.

Source: http://en.wikipedia.org/wiki/Moore%27s_paradox

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Categories: General Knowledge, Science

345/365 – Time

August 9, 2012 Leave a comment

Time is the continuing progression of events occurring in apparently irreversible succession from the past through the present to the future, and a measure of the durations and frequencies of events and the intervals between them.

Time has long been a major subject of study in religion, philosophy, and science, but defining it in a manner applicable to all fields without circularity has consistently eluded scholars.

Nevertheless, diverse fields such as business, industry, sports, the sciences, music, dance, and the live theater all incorporate some notion of time into their respective measuring systems.

Some simple, relatively uncontroversial definitions of time include “time is what clocks measure” and “time is what keeps everything from happening at once”.

Two contrasting viewpoints on time divide many prominent philosophers. One view is that time is part of the fundamental structure of the universe, a dimension in which events occur in sequence.

Sir Isaac Newton subscribed to this realist view, and hence it is sometimes referred to as Newtonian time. Time travel, in this view, becomes a possibility as other “times” persist like frames of a film strip, spread out across the time line.

The opposing view is that time does not refer to any kind of “container” that events and objects “move through”, nor to any entity that “flows”, but that it is instead part of a fundamental intellectual structure (together with space and number) within which humans sequence and compare events.

This second view, in the tradition of Gottfried Leibniz[14] and Immanuel Kant, holds that time is neither an event nor a thing, and thus is not itself measurable nor can it be travelled.

Time is one of the seven fundamental physical quantities in the International System of Units. Time is used to define other quantities — such as velocity — so defining time in terms of such quantities would result in circularity of definition.

An operational definition of time, wherein one says that observing a certain number of repetitions of one or another standard cyclical event (such as the passage of a free-swinging pendulum) constitutes one standard unit such as the second, is highly useful in the conduct of both advanced experiments and everyday affairs of life.

The operational definition leaves aside the question whether there is something called time, apart from the counting activity just mentioned, that flows and that can be measured.

Investigations of a single continuum called spacetime bring questions about space into questions about time, questions that have their roots in the works of early students of natural philosophy.

Furthermore, it may be that there is a subjective component to time, but whether or not time itself is “felt”, as a sensation or an experience, has never been settled.

Source: http://en.wikipedia.org/wiki/Time

Categories: General Knowledge, Science

342/365 – Nuclear Medicine

August 6, 2012 Leave a comment

Nuclear medicine is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease.

In nuclear medicine procedures, radionuclides are combined with other elements to form chemical compounds, or else combined with existing pharmaceutical compounds, to form radiopharmaceuticals.

These radiopharmaceuticals, once administered to the patient, can localize to specific organs or cellular receptors.

This property of radiopharmaceuticals allows nuclear medicine the ability to image the extent of a disease process in the body, based on the cellular function and physiology, rather than relying on physical changes in the tissue anatomy.

In some diseases nuclear medicine studies can identify medical problems at an earlier stage than other diagnostic tests.

Nuclear medicine, in a sense, is “radiology done inside out” or “endo-radiology” because it records radiation emitting from within the body rather than radiation that is generated by external sources like X-rays.

Treatment of diseased tissue, based on metabolism or uptake or binding of a particular ligand, may also be accomplished, similar to other areas of pharmacology.

However, the treatment effects of radiopharmaceuticals rely on the tissue-destructive power of short-range ionizing radiation.

In the future nuclear medicine may provide added impetus to the field known as molecular medicine. As understanding of biological processes in the cells of living organism expands, specific probes can be developed to allow visualization, characterization, and quantification of biologic processes at the cellular and subcellular levels.

Nuclear medicine is a possible specialty for adapting to the new discipline of molecular medicine, because of its emphasis on function and its utilization of imaging agents that are specific for a particular disease process.

Source: http://en.wikipedia.org/wiki/Nuclear_medicinea

Categories: General Knowledge, Science

321/365 – Homeopathy

1 – Hippocrates ‘The Father of Medicine’ of Ancient Greece said there were two Laws of Healing: The Law of Opposites and the Law of Similars. Homeopathy treats the patient with medicines using the Law of Similars, orthodox medicine uses the Law of Opposites, e.g. antibiotics, anti-inflammatories, anticonvulsants, antihypertensives, anti-depressants, anti-psychotics.

2 – Homeopathic theories are based on fixed principles of the Laws of Nature which do not change — unlike medical theories which are constantly changing!

3 – Homeopathy is an evidence-based, empirical medicine.

4 – Homeopathy is both an art and a science.

5 – The Homeopathic provings of medicines are a more scientific method of testing than the orthodox model.

6 – Homeopathic medicine awakens and stimulates the body’s own curative powers. The potentized remedy acts as a catalyst to set healing into motion.

7 – Homeopathic medicines work by communicating a current/pattern/frequency of energy via the whole human body to jump start the body’s own inherent healing mechanisms.

8 – Homeopathy assists the body to heal itself, to overcome an illness which brings the patient to a higher level of health. Orthodox medicine suppresses the illness, bringing the patient to a lower level of health.

9 – The homeopathic practitioner endeavours to search for and treat the cause of the disease in order to heal the effect.

10 – Outcomes of homeopathic treatment are measured by the long term curative effects of prescribing and complete eradication of the disease state.

11 – The homeopathic practitioner treats the whole person, believing all symptoms are interrelated and seeks to select a medicine which most closely covers them all.

Source: http://www.naturalnews.com/024512_homeopathic_homeopathy_medicine.html

Categories: General Knowledge, Science

310/365 – Theory of Evolution

Evolution is any change across successive generations in the inherited characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.

Life on Earth originated and then evolved from a universal common ancestor approximately 3.7 billion years ago. Repeated speciation and the divergence of life can be inferred from shared sets of biochemical and morphological traits, or by shared DNA sequences.

These homologous traits and sequences are more similar among species that share a more recent common ancestor, and can be used to reconstruct evolutionary histories, using both existing species and the fossil record.

Existing patterns of biodiversity have been shaped both by speciation and by extinction.   Charles Darwin was the first to formulate a scientific argument for the theory of evolution by means of natural selection.

Evolution by natural selection is a process that is inferred from three facts about populations:

1) more offspring are produced than can possibly survive,

2) traits vary among individuals, leading to differential rates of survival and reproduction, and

3) trait differences are heritable.

Thus, when members of a population die they are replaced by the progeny of parents that were better adapted to survive and reproduce in the environment in which natural selection took place.

This process creates and preserves traits that are seemingly fitted for the functional roles they perform. Natural selection is the only known cause of adaptation, but not the only known cause of evolution.

Other, nonadaptive causes of evolution include mutation and genetic drift.   In the early 20th century, genetics was integrated with Darwin’s theory of evolution by natural selection through the discipline of population genetics.

The importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis and “progress” became obsolete.

Scientists continue to study various aspects of evolution by forming and testing hypotheses, constructing scientific theories, using observational data, and performing experiments in both the field and the laboratory.

Biologists agree that descent with modification is one of the most reliably established facts in science. Discoveries in evolutionary biology have made a significant impact not just within the traditional branches of biology, but also in other academic disciplines (e.g., anthropology and psychology) and on society at large.

Source: http://en.wikipedia.org/wiki/Evolution

Categories: General Knowledge, Science

308/365 – Higgs Boson

The Higgs boson is a hypothetical elementary particle predicted by the Standard Model (SM) of particle physics. It belongs to a class of particles known as bosons, characterized by an integer value of their spin quantum number.

The Higgs field is a quantum field that fills all of space, and explains why fundamental particles such as quarks and electrons have mass. The Higgs boson is an excitation of the Higgs field above its ground state.

The existence of the Higgs boson is predicted by the Standard Model to explain how spontaneous breaking of electroweak symmetry (the Higgs mechanism) takes place in nature, which in turn explains why other elementary particles have mass.

Its discovery would further validate the Standard Model as essentially correct, as it is the only elementary particle predicted by the Standard Model that has not yet been observed in particle physics experiments.

The Standard Model completely fixes the properties of the Higgs boson, except for its mass. It is expected to have no spin and no electric or color charge, and it interacts with other particles through weak interaction and Yukawa interactions.

Alternative sources of the Higgs mechanism that do not need the Higgs boson are also possible and would be considered if the existence of the Higgs boson were ruled out. They are known as Higgsless models.

Experiments to determine whether the Higgs boson exists are currently being performed using the Large Hadron Collider (LHC) at CERN, and were performed at Fermilab’s Tevatron until its closure in late 2011.

Mathematical consistency of the Standard Model requires that any mechanism capable of generating the masses of elementary particles become visible at energies above 1.4 TeV; therefore, the LHC (designed to collide two 7-TeV proton beams) is expected to be able to answer the question of whether or not the Higgs boson actually exists.

In December 2011, Fabiola Gianotti and Guido Tonelli, spokespersons of the two main experiments at the LHC (ATLAS and CMS) both reported independently that their data hints at a possibility the Higgs may exist with a mass around 125 GeV/c2 (about 133 proton masses, on the order of 10−25 kg).

They also reported that the original range under investigation has been narrowed down considerably and that a mass outside approximately 115–130 GeV/c2 is almost ruled out. No conclusive answer yet exists, although it is expected that the LHC will provide sufficient data by the end of 2012 for a definite answer.

On 22 June, 2012, CERN announced they would hold a press conference on the topic on 4 July, 2012.

In the popular media, the particle is sometimes referred to as the God particle, a title generally disliked by the scientific community as media hyperbole that misleads readers.

Source: http://en.wikipedia.org/wiki/Higgs_boson

Categories: General Knowledge, Science

293/365 – Left handedness

Possible advantages of left-handedness  

Some studies have shown that “…left-handers also tend to have unusually good visual-spatial skills and the ability to imagine spatial layouts.”

Santrock goes on to point out that mathematicians, musicians, architects, and artists are more commonly left-handers than would be expected.

“Also, in one study of more than 100,000 students taking the Scholastic Aptitude Test (SAT), 20% of the top-scoring group was left-handed, twice the rate of left-handedness found in the general population (10%). Left-handedness may also reduce the risk of developing arthritis.

However, Hardyck and Petrinovich reviewed a large literature and found no overall differences in mental ability in right-handers and non-right-handers.

Other reported associations include with higher creativity, a larger corpus callosum, certain right brain regions being larger, shorter transfer time of information between hemispheres, and higher socioeconomic status.

Possible disadvantages of left-handedness  

Although there is little association with children’s school performance in regards to handedness, some studies have shown problems in language development in left-handers.

Research has shown left-handers are more likely to have problems with reading and they also “…don’t do as well on phonology (the sound system of language) tasks…” when compared with right-handers.

Also, in left-to-right languages, as the left-handed writer moves their left hand across the place where they have just written, smudging may occur, though this was mainly a concern in older technologies such as fountain pen usage. This situation is reversed in right-to-left languages such as Hebrew and Arabic.

Other reported associations that may have decreased evolutionary fitness include shorter adult height, lower weight, puberty at a later age, possibly a shorter life expectancy, increased risk of accidents, increased risk of certain neurological and immunological disorders, and decreased number of children.

Source: http://en.wikipedia.org/wiki/Handedness