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En logique mathématique, on appelle problème de la décision ou, sous son nom d'origine en allemand, , le fait de déterminer de façon mécanique (par  un algorithme) si un énoncé est un théorème de la logique égalitaire du premier ordre, c'est-à-dire s'il se dérive dans un système de déduction sans autres axiomes que ceux de l'égalité (exemples : système à la Hilbert, calcul des séquents, déduction naturelle). De façon équivalente par le théorème de complétude, il s'agit finalement de savoir si un énoncé est universellement valide, c'est-à-dire vrai dans tous les modèles (de l'égalité).

Le problème de la décision est un exemple de problème de décision : une question de décidabilité au sens algorithmique. Ici la question est celle de la décidabilité du calcul des prédicats égalitaire du premier ordre : l'ensemble des énoncés universellement valides du calcul des prédicats du premier ordre est-il décidable ?

Le problème de la décision dépend en fait du choix du langage du premier ordre : sa signature, les « briques » de base qui permettent la construction des énoncés, les symboles de constantes, de fonctions (ou opérations), et de prédicat (par exemple 0, +, ≤…).

Dans un langage donné (exemple : dans l'arithmétique de Peano, c'est le langage arithmétique), une solution positive AU problème de la décision fournit une solution positive AUX problèmes de la décision pour toutes les théories finiment axiomatisables de ce langage. En effet, un énoncé C se déduit d'un système fini d'axiomes si et seulement si on peut dériver en logique pure que la conjonction de ces axiomes entraîne C.

Histoire
La question du problème de décision remonte à Gottfried Wilhelm Leibniz qui, au , imaginait la construction d'une machine qui pouvait manipuler des symboles (qui plus tard seront ceux de constantes, de fonctions…) afin de déterminer les valeurs des énoncés mathématiques. Il comprit que le premier pas serait d'avoir un langage formel clair (dont le problème dépend).

En 1928, David Hilbert et Wilhelm Ackermann posent le problème de la décision tel que nous le connaissons aujourd'hui.

En 1936, Alan Turing et Alonzo Church donnent chacun une réponse négative à ce problème pour l'arithmétique.

Exemple : arithmétique de Peano
On parle aussi du problème de la décision dans une théorie axiomatique donnée, par exemple dans l'arithmétique de Peano. Il s'agit alors de déterminer si un énoncé est un théorème de la théorie en question.

Alonzo Church et Alan Turing donnèrent (indépendamment) en 1936 une réponse négative au problème de la décision pour l'arithmétique (par exemple l'arithmétique de Peano). Ils déduisirent par codage une réponse négative pour le problème de la décision dès que le langage contient un symbole de prédicat binaire (en plus de l'égalité).

Par contre, si le langage ne contient que des symboles de prédicats unaires et des symboles de constantes (pas de symboles de fonctions), alors le calcul des prédicats du premier ordre égalitaire correspondant, le calcul des prédicats monadiques du premier ordre, est décidable.

Par ailleurs, il existe des théories décidables dont le langage contient un symbole de prédicat binaire : la théorie des ordres denses (celle de l'ensemble des rationnels  dans le seul langage de l'ordre) pour prendre un exemple très simple, ou encore l'arithmétique de Presburger.

Alonzo Church
Pour répondre de manière négative à la question, Church s'appuie essentiellement sur le théorème de Gödel-Rosser et des méthodes développées par Gödel pour démontrer le premier théorème d'incomplétude. Le résultat énoncé est :

Les conditions précises du théorème sont celles du théorème de Gödel-Rosser. Si on les examine, on se rend compte qu'elles sont réalisées par une théorie finiment axiomatisable. Un énoncé est démontrable dans une telle théorie si et seulement si la conjonction des axiomes de cette théorie entraîne cet énoncé. On obtient ainsi une réponse négative au problème de la décision dans le langage de l'arithmétique (on peut prendre 0, 1, + , ×).

Alan Turing
Rappelons l'apparition de plusieurs modèles de calcul dans les années 1930 (on peut citer les fonctions λ-calculables de Church (1930), les fonctions récursives générales de Herbrand et Gödel (1931 - 1934), les machines de Turing (1936)), qui se révèlent être tous équivalents, et permettent de définir une fonction calculable, c'est-à-dire qui se calcule mécaniquement, par un algorithme par exemple.

Pour montrer l'indécidabilité de l'arithmétique, l'argumentation d'Alan Turing est la suivante : il suppose par l'absurde avoir un algorithme de décision pour l'arithmétique de Peano. Or la question de savoir si une machine de Turing donnée s'arrête ou non peut s'écrire comme énoncé de premier ordre (grâce aux méthodes développées par Gödel). Alors cet énoncé sera résolu par l'algorithme de décision. Or Turing avait démontré qu'il n'existe aucun algorithme pour décider de l'arrêt d'une machine de Turing. Il y a absurdité : le calcul des prédicats du premier ordre égalitaire dans le langage arithmétique est indécidable.

Voir aussi
 Problème de décision
 Théorème d'incomplétude de Gödel

Références

Sources

En français

 Jean-Pierre Azra et Bernard Jaulin, Récursivité, Gauthier-Villars, 1973

En anglais
 S. C. Kleene - Introduction to metamathematics - Elsevier - 1952  -  (réédité)
M. Davis - The undecidable - 2004

Articles originaux

  et

Décision
Logique mathématique

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receive glory and honor and power, for You created all things, and by Your will they were created and,have their being."
We go to church and sing songs of praise and worship. We lift our hands to the Lord. We sing of our love for Him. The music swells, our voices raise to the rafters. We speak the words to the songs and make a joyful noise to our Creator.
But where is our heart? Are our hearts in tune with the words? Do our thoughts flow to the Lord or are they on what is for dinner and what needs done when we get home?
At the church I attend, we have a time at the beginning of the service to calm our thoughts and take time to focus on the Lord. I find that time is not utilized to it's full potential. I find myself settling in and finding the first hymn and the scripture reference for that sermon. I try to refocus during the first few minutes of the service and miss some things I need to hear. I need to prioritize better, so that my focus is on worship.
We sing to the Lord that He is worthy of our praise, but is our praise worthy of Him? Is our heart set to give Him our full attention? The Lord is meant to be at the center of our lives and yet we offer Him the remnants of our thoughts and time. We sing to Him with our thoughts elsewhere when we should be offering Him a mansion of praise.
He gives us 24/7 attention. He is there all the time. No matter what we do or where we are, He is in the midst of our lives. He shares our mountain tops and our deep valleys. He knows our thoughts and deeds. He is worthy of our praise and worship and love. He is all we need.


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Tiger Zinda Hai Movie Review: Salman Khan and Katrina Kaif offer a thrilling ride
Tiger Zinda Hai starring Salman Khan and Katrina Kaif and directed by Ali Abbas Zafar is a complete Salman Khan show. Salman Khan fans will find Tiger Zinda Hai thoroughly entertaining. The film deserves a watch for its sleek action sequences.
Ananya Bhattacharya
UPDATED: April 16, 2019 18:43 IST
Tiger Zinda Hai Movie Review
Movie Name: Tiger Zinda Hai
Cast: Salman Khan, Katrina Kaif
Director: Kabir Khan
"Aaj kal RAW mein comedy chal rahi hai?" asks Tiger to Karan (Anant Vidhaat Sharma), when the latter tells him the code "Tu Tu Tu Tu Tu Tara." Tiger's words are strangely prophetic. In the course of Ali Abbas Zafar's Tiger Zinda Hai, we see many instances that might make us echo Tiger. But who cares. This is a classic Salman Khan show. Aimed at undoing all the hatke, different Salman that we saw in Tubelight earlier this year. This is the Khan that his fans want on the big screen. To be able to whistle to the ripple of his every sinew as his muscles dance in tandem with the trigger, to be able to cheer for Salman as he fights off a pack of wolves alone.
Salman, the superhero, is back.
"Tiger zinda hai" is uttered thrice in the film, by various people, with various expressions. The film begins with Siddharth Basu's surprised"Tiger zinda hai?" when Shenoy (Girish Karnad) tells him that only Tiger can get 25 Indian nurses out of the ISC (an Islamist terrorist organisation modelled on the ISIS) hands in Ikrit (after Tikrit where the real incident unfolded), Iraq. They have only eight days for this mission, before the US orders airstrikes on the city. And only Tiger can make the impossible possible. But Tiger has been missing for the last eight years. He is safely nestled in snowy Innsbruck, where he now lives in a log cabin with his wife and ex-ISI agent, Zoya (Katrina Kaif) and son, Junior.
Salman Khan is given a lavish introduction scene featuring wolves, who hunt in packs, we are told. He, Tiger, hunts alone. As he fights off about eight to nine wolves single-handedly and shows off some exceptional snowboarding skills, we realise that Tiger abhi zinda hai.
After that, senior RAW officer Shenoy reaches his cabin in the mountains and tells him that he has to do it. For the country. It takes exactly ten seconds of convincing from his wife Zoya for Tiger to say yes to this mission.
He brings his own three-member team along, to the deserts of Abu Dhabi from where they are to set off for Ikrit. Angad Bedi, Paresh Pahuja and Kumud Mishra's characters form the other wheels, along with Katrina Kaif, of this vehicle that has Salman Khan firmly on the steering wheel, from beginning to end.
Writer-director Ali Abbas Zafar taps into Salman Khan's strengths as an actor... strike that. As a hero. And delivers one of the best, quintessentially Salman Khan films in recent times. Salman beats up five hundred trained ISC terrorists and unleashes destruction on the organisation. He tells their leader Abu Usman (modelled on ISIS's self-styled Caliph Abu Bakr Al Baghdadi, and played by Sajjad Delafrooz, in an impressive Bollywood debut) that a wounded tiger is dangerous. He rescues the Indian nurses and takes care of the twists too.
Salman Khan is every bit the superhero in Tiger Zinda Hai that his fans have been waiting with bated breath for this entire year. Whatever Salman-ness Tubelight deprived his fans of, Tiger Zinda Hai pours on them in abundance. At 161 minutes, a little too much.
Katrina Kaif is a delight to watch when she is kicking and sending people flying in the air. Or when she is flying her car. Kaif's acting skills, sadly, have not changed one bit since Tiger and Zoya disappeared from RAW and ISI's radars all those years ago and we saw the end of Ek Tha Tiger.
The supporting cast is not left with much to do, given that Salman Khan hogs both the camera as well as the guns. Apart from some hamming from Paresh Rawal; Angad Bedi, Kumud Mishra, Anupriya Goenka and Paresh Pahuja all blend into their roles. And help Tiger prance forward with all his might. Sajjad Delafrooz shines as Abu Usman.
Tiger Zinda Hai takes off from where Ek Tha Tiger ended. But given that director Kabir Khan left the prequel open to another film, Ali Abbas Zafar doesn't have to spend a lot of time explaining in Tiger Zinda Hai where Tiger and Zoya have been all these years.
The film has logical loopholes the size of craters. But a person choosing to watch a Salman Khan show might already be aware of that. Don't analyse, don't nitpick, don't involve logic; and you are sorted. There are many seeti-worthy moments in Tiger Zinda Hai. The film plays to Salman's gallery to the T.
From the Austrian Alps to the deserts of Abu Dhabi which pass off as Iraq in the film, cinematographer Marcin Laskawiec has a firm grip on the camera.
Ali Abbas Zafar's camera, on the other hand, is focused solely on Tiger. His every muscle is magnified, every flexing slowed down for complete, total impact. He comes out after killing dozens of people and fighting a few more, but his hair is salon-perfect. You cannot miss Salman Khan in Tiger Zinda Hai. You are not allowed to.
The music works in favour of Tiger Zinda Hai. There are not many songs that are used during the primary run-time of the film. Tera Noor by Jyoti Nooran deserves a special mention.
The second time the sentence 'Tiger zinda hai' is used in the film, is to express shock. The third, as assurance. Tiger abhi zinda hai. And the box office will raise a toast to that. Why care about the RAW?
(The writer tweets as @ananya116)
ALSO WATCH: Katrina talks about working with Salman in Tiger Zinda Hai
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After its launch in 2010, Instagram made and maintained a space for itself with its special filters and a few more unique features including its user experience optimized for mobile and a "safe environment" for its users.
Back to why I started writing this post, let's take a close look at some of the latest features on the app and how they come in handy for users and most especially businesses on Instagram.
I know right, hashtags have existed like forever, but there are quite a few cool things you could do with hashtags on Instagram. With the new update to Instagram stories, you can now add and edit hashtag stickers on your Instagram story, how cool is that? With this feature, other users can find your story by searching for stories by hashtag and location in the explore feed.
With this cool feature available in recent Instagram updates, you can now bookmark (or save) any image you like and want to see later. By simply clicking the bookmark icon on the bottom-right corner of an image of video and voila! You view this anytime you want to. With the latest version of Instagram, you can group your saved images into "collections" like Dance, Fashion even Food.
The Story Poll is one of the newest members of the family and for businesses on Instagram, this is one great feature and here's why. The Story Poll allows you create a survey on your Instagram story and get feedback from your followers. If I owned a fashion store on Instagram, I could get my followers to give their feedback on new arrivals or choose the perfect look for my Friday happy hour.
Now, it's amazing to know that you can now (or very soon) sell directly on Instagram without your customers leaving the app or visiting any website. Although this feature is only available to selected users only in the US, to use this feature you must first "enable shopping" in your business profile.
If you are as scared as me about waking up to find your Instagram account gone, this is one feature you don't want to jump over. Although this feature is not particular to Instagram, Two-factor authentication (2FA) is one of the essential security protocols to use for any service. And Instagram now supports it, so turn it on.
There are probably over 20 more features I could on about, but I planned to make this a short read and try not to rant about how Instagram and Snapchat keep copying each other lol . Maybe I'll in my next post.
Do you know about other amazing features you'll like to share? I can't wait to read your comments below.


OMAHA, Neb. — All four members of a Topeka, Kansas family recently found themselves as patients at Nebraska Medicine for different reasons. While 33-year-old Brady Sorensen was recovering from a liver transplant his wife, Jess, went into premature labor with their twin girls.


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Foundations of sand?
Christian Jarrett on the lure of academic myths and their place in classic psychology
Other sciences have their cardinal theories – of relativity, of evolution, the big bang, to name but three. Psychology has its theories too, of course. But arguably psychology's foundations are built not of theory but with the rock of classic experiments – Asch's 'conformity studies', the Stanford Prison Experiment, Little Albert, Milgram, the Hawthorne studies, the bystander effect… the list goes on. So important to psychology are these experiments that they've acquired an almost mythical status. And like myths, the way some of them have been told has shifted and distorted with time. Some psychologists have noticed this trend, and they're doing their best to correct the misunderstandings – which they say could be harmful to our science.
The helpful witnesses
You'll be hard-pressed to find a psychology textbook that doesn't tell the sad story of Kitty Genovese's murder in the Kew Gardens neighbourhood of New York in 1964. Most will describe the shocking details of how there were 38 witnesses to the stabbing, all of them residents in the apartment block overlooking the scene of the crime, all of whom did nothing. Genovese's tragedy inspired the psychologists Bibb Latané and John Darley to formulate and test their theory that people's sense of social responsibility is diluted when they are in a group – the bystander effect.
The bystander effect itself has since been supported by ample research, but a paper published last year in American Psychologist by Rachel Manning at the University of the West of England and colleagues uncovered fresh historical research showing how the story of Kitty Genovese, as it's usually told, is actually something of a myth (see box). In short, probably only one person witnessed the final, fatal stabbing and several witnesses did do something to help.
'Given the iconic status of the 38 witnesses story, I wanted to find out more about the place where this incident occurred,' says Manning. 'Having looked through the, interestingly, fairly limited information available in textbooks and journal articles, I trawled the internet, looking for photos and any other information I could find about Kew Gardens. I came across Joseph De May's local history website (www.oldkewgardens.com)... Joe had started to examine the 38 witnesses story as a clearly difficult but important aspect of the history of Kew Gardens.'
The commonly told inaccuracies in the Kitty Genovese tale stem from the New York Times article which first broke the news. No doubt this version of what happened, shocking as it is, has subsequently served textbook writers well, seeking as they do to link experimental research with the real world in an engaging way. This begs the question: if the distortions have survived largely through accident or convenience, and if the actual bystander effect has been supported by subsequent research, does it matter that the tale of Kitty Genovese is not entirely rooted in reality?
Manning's group say it does because the power of the Genovese story has reinforced the notion that crowds are dangerous (in this case through their alleged inaction), thereby inhibiting research on the potential positive aspects of group behaviour. Manning hopes her article will help to redress the balance.
'Since the publication of our article, we have been contacted by a number of people, including textbook writers, who are happy to correct the historical record,' Manning says. 'However, some people remain quite attached to it and are reluctant to challenge its veracity.'
The power of independence
Another psychology classic retold in any textbook you happen to sample are the so-called Asch 'conformity experiments', in which lone participants, embedded in groups of confederates working for the researcher, were asked to compare the lengths of lines. The key test was whether participants would go along with a majority opinion that was clearly wrong.
Your chosen reference will no doubt inform you that Solomon Asch's experiments provide a striking illustration of the power of social conformity. Indeed, a fourth edition of Richard Gross's Psychology: The Science of Mind and Behaviour on my bookshelf quotes social psychologist van Avermaet stating unequivocally: 'The [Asch] results reveal the tremendous impact of an "obviously" incorrect but unanimous majority on the judgements of a lone individual.'
But is that really what the results showed? A paper published in 1990 by Ronald Friend (now emeritus professor at Stony Brook University) and colleagues, contends that Asch actually saw his results as a demonstration of the power of independence (see box). Interpreting his results, Asch wrote in 1952: '…the facts that were being judged were, under the circumstances, the most decisive.'
Of course, a degree of subjectivity is inevitable – one reader might focus on what they see as the remarkable number of participants who stayed independent, while another marvels at the number who yielded. Given this scope for varying interpretation, the most important aim for any author, presumably, is to report the results in an unbiased fashion – something an analysis of textbooks by Ronald Friend and Yvonne Rafferty in 1985 showed hasn't tended to happen.
Over half the 99 textbooks sampled quoted the percentage of responses in which participants yielded to the group majority, without even mentioning the
far larger proportion of responses which went against the mistaken herd (only one writer showed the opposite bias). As regards individual differences, 42 per cent of books gave greater emphasis to quoting the number of participants who conformed, while just 5 per cent showed the opposite bias. Another misleading habit has been to flag up the percentage of participants who yielded to majority opinion at least once (76 per cent), without providing the opposite figure – the 95 per cent of participants who stayed independent at least once.
Others have challenged the whole conformity versus independence debate as overly simplistic. Bert Hodges and Anne Geyer published a paper in 2006 in which they argued the most interesting participants in Asch's studies were those – the majority, in fact – who sometimes yielded to the majority opinion but sometimes stayed independent, as they attempted pragmatically to balance the demands of an extremely awkward social situation. According to Hodges and Geyer's account, giving the occasional false answer, in line with majority opinion, might actually represent the best strategy for persuading others of the truth of your own claims, by showing them that their judgments are relevant and have been noted.
Yvonne Rafferty (Psychology Professor at Pace University in New York) says the misinterpretation of Asch's experiments continues to this day, even finding a voice on the internet. 'I just Googled "Asch Study Social Psychology",' Rafferty says, and the top link [tinyurl.com/6pjmma] brought me to a blog site that states "Solomon Asch's classic... social psychology experiment shows that many of us will deny our own senses just to conform with others".' Rafferty notes that Wikipedia propagates the same line, even suggesting that Asch's experiments provide an empirical basis for the ideas on conformity in George Orwell's 1984.
Why do people who write about classic psychology experiments want to propagate the idea that we're all prone to becoming mindless sheep in the face of a majority opinion? Rafferty believes part of the answer lies in the headline appeal of the notion that conformity is all powerful. But beyond that she wonders if there lies a darker motive. 'Why is individualism so overvalued by society – what threat do organisations perceive if we are not viewed as sheep?', Rafferty asks. 'Is there perhaps such a fear of social movements by which we might come together for a common cause?'
Echoing Manning's views on the influence of the Genovese myth, Rafferty believes that the misreporting of the Asch experiments has had a harmful effect on the direction taken by social psychology research. 'In overemphasising the powerful but detrimental effect of the group on the individual, the discipline of social psychology may have inadvertently undermined its potential usefulness in showing the practical contribution and positive benefits that groups can have for individuals,' Rafferty says.
Conditioning babies
You'd be forgiven at this point for thinking that it is exclusively social psychology that suffers from the lure of academic myths. Not so. One of the most consistently misreported studies in psychology is the tale of Little Albert and his conditioning by John Watson and Rosalie Rayner in 1920. For decades the case has been heralded as the classic example of how humans, like animals, can be easily led to fear innocuous stimuli using classical conditioning, and how this fear generalises to other similar stimuli according to the rules of behaviourism.
Unfortunately, Watson and Rayner's study was conducted in a haphazard fashion (see box) – a fact neglected by most textbooks. To give one example: It is often reported that Albert's conditioned fear of white rats generalised to, among other things, a fear of dogs. The reality is that Albert was initially unmoved when, after his conditioning, a dog was first brought into the laboratory. After that, the dog, previously silent, barked three times loudly just six inches from Albert's face. In the words of the original 1920 report, not only was Albert upset, but 'The sudden barking of the hitherto quiet dog produced a marked fear response in the adult observers!' This was hardly an appropriately controlled test of Albert's conditioned fears.
Authors have also invented stimuli that Albert was never tested on, including a cat, a man's beard, a white furry glove, his aunt, a teddy bear, as well as the oft-cited claim that he became fearful of all 'furry animals'. Another curious error is that textbook authors have tended to claim that Albert's mother withdrew him from Watson and Rayner's care before they had a chance to extinguish his fears using desensitisation. The truth, apparent from the original 1920 report, is that Watson and Rayner knew a month in advance when Albert would no longer be available.
'These inaccuracies definitely do still exist,' says Professor Benjamin Harris at the University of New Hampshire, author of a landmark critique of the Little Albert story published in 1979 entitled 'Whatever happened to Little Albert?' 'There are still people out there who want to give an easy explanation for things like stimulus generalisation in classical conditioning,' says Harris 'and it is just too inviting an idea that something like white objects or furry objects are going to be fear arousing because of the process of stimulus generalisation.'
Could the misreporting of the Little Albert story have damaged progress in psychology in the same way that Manning and Rafferty believe academic myths have inhibited certain lines of research in the social domain? According to Harris, this depends on the extent to which you believe behaviourism continues to exert an unjustified influence on contemporary psychological thought. 'You could argue that it makes people complacent, leading them to think simplistically about PTSD or other forms of adult psychopathology,' he says.
Beyond his 1979 paper, Harris has devoted great energies to correcting the mis-telling of the Little Albert story, unfortunately with little success. For example, Harris worked to ensure the tale was told accurately by Philip Zimbardo in the 1990s Discovering Psychology TV series broadcast on American Television. Harris sold the show producers the rights to footage of the Watson and Rayner study, which he had serendipitously discovered under a stairwell at the University of Michigan. But instead of this serving to improve the veracity of the programme, the producers edited the clip in such a way to make it appear that Watson had in fact conditioned two children, not just one, a misleading impression reinforced by Zimbardo's narration!
The 'whatever' effect
A true sign that a study or studies have acquired mythical status is when they lend their name to an 'effect'. So it is with the 'Hawthorne effect', a name derived from a series of experiments on productivity conducted at the Hawthorne Works of the Western Electric Company in Chicago, in the late 1920s, early 1930s. But according to Mecca Chiesa at the University of Kent and Sandy Hobbs at the University of West of Scotland, the fame of these studies is not matched by their quality (see box). The pair published a critique this year in which they lamented the thriving, widespread use of the term in light of its hopelessly vague meaning and given that the original Hawthorne studies were woefully poor.
Chiesa and Hobbs sampled over two hundred books published between 1953 and 2003 and found an astonishingly broad range of uses for the term 'Hawthorne effect', with many such meanings actually contradicting each other. In some cases the term was used to imply that simply being the subject of an investigation can enhance workers' performance. Elsewhere the term was used more specifically, to refer to the presence of a 'warm climate', the 'presence of an observer', 'concern' or merely 'friendly supervision'. Moreover, there were widespread inconsistencies in how the effects were supposed to exert their influence, with some accounts suggesting an unconscious effect, while others pointed to 'feelings of pride' or 'job satisfaction'.
Chiesa says she first became interested in the Hawthorne effect after hearing the same comment over and over in response to research she was involved in. 'Finally, when I was asked by a journal editor to respond to "the potential criticism that our findings were an example of the Hawthorne effect" I thought it was time to have a closer look,' she says. 'That was when I discovered that just about everything and anything was speculated to cause improvement in human performance.'
Hobbs says he thinks a key part of the problem causing the perpetuation of myths in general and of the Hawthorne effect in particular is people's reliance on secondary sources. 'People read something, don't question it and that then leads to poor quality knowledge. The concept is appealing, but there's this reification – once something's got a name it somehow seems more concrete and real.'
He adds that the rise of the internet may have added to this problem, especially as it makes it so much harder to gauge the veracity of a source. 'When I was a student you looked at the Daily Express and at a journal and there was a clear difference – you're setting out with assumptions about what the standards are. But now you can get websites that look neat and clean but the content is pretty much valueless.'
Putting psychology on the couch
Other sciences certainly do have their own myths – just think of the story of Newton and the falling apple or Archimedes leaping out of the bath following his Eureka insight. Perhaps myths just seem more prominent in psychology because we tend to talk and write about our science in terms of studies rather than facts. Certainly the work of Mary Smyth at Lancaster University would appear to be consistent with this view – she has compared psychology and biology textbooks and found that psychology appears to have comparatively few taken-for-granted facts. Instead, numerous experiments are described in detail, lending scientific credence to any factual claims being made.
Related to this, there's no doubt that the actual subject matter of psychology plays a part too – there's that ever-present pressure to demonstrate that psychological findings are more than mere common sense. Benjamin Harris says that historians have described psychology as putting a scientific gloss
on the accepted social wisdom of the day. 'Psychology is always going to have a strong social component,' he explains. 'With psychological theories speaking to the human condition, there's always going to be an appeal to myths that resonate more with experience than something coming out of the lab that's sterile and ultra scientific.'
Another role that myths play is to reinforce the empirical legitimacy of psychology and to create a sense of a shared knowledge base. 'In this way, tales such as of Kitty Genovese or Little Albert are rather like origin myths, pushing the creation of psychology, or a particular approach within psychology back in time, thus giving an air of greater authority,' says Harris.
Hobbs agrees: 'It's nice to have something that you can take for granted,' he says. 'In the case of the Hawthorne effect and other myths, you shouldn't take it for granted, but it's comforting to be able to say "Oh, this could be the Hawthorne effect" and for others to nod and say "Ah yes, that's right".'
But if, as we've seen, these myths are harmful to psychology – for example, inhibiting potential fruitful lines of research, or leading to meaningless criticisms of submitted papers – then shouldn't we be doing more to set the record straight? Harris is philosophical: 'The more time I spend studying the history of psychology, the more I just enjoy standing on the sideline and watching psychologists argue about the myths – that itself becomes part of the interesting history of the science,' he says. 'You get to see how psychologists' understanding of human nature has its fashions, it's always dynamic.'
Hobbs, though, thinks we should be doing more. 'There isn't any sense of a field of study looking at the myths of psychology and I think that's regrettable. I think if there were it would make people be more on their guard.'
BOX: The bystander effect
Drawing on De May's research, Rachel Manning's group suggest the truth of the story is that there weren't 38 witnesses; probably only one person saw the final, fatal attack; and the police were called. Much of the fresh evidence comes from transcripts of the trial in which Winston Moseley was charged with Genovese's murder. None of the three witnesses who were called reported seeing the stabbing; in fact, Moseley's final, fatal attack took place inside the apartment block, out of the view of all but one of the known witnesses. And contrary to the popular notion that no one did anything to help, one of the witnesses claims to have shouted at Moseley, scaring him off from his initial attack – a claim corroborated by a second witness. Moreover, a former police officer – a 15-year-old eyewitness at the time of the murder – says that his father called the police.
BOX: Asch's conformity experiments
Groups of between six and nine people were asked to match, out loud, a target line, according to length, with one of three comparison lines. All bar one of the group members were actually accomplices working for Asch, and on 12 of 18 trials they were instructed to unanimously match the target line with the wrong comparison line. The majority of participants' responses (63.2 per cent vs. 36.8 per cent) went against the erroneous majority. Another way Asch measured outcomes was to examine individual differences. This showed that just 5 per cent of participants were always swayed by majority opinion whereas 25 per cent of the sample consistently stuck to their guns.
Though rarely reported, Asch's research also included the collection of qualitative data via interviews. Many participants said that although they had agreed with the group on occasions, they were certain all along that the group were wrong. This confirms the idea that participants hadn't actually been persuaded by the erroneous group majority, but rather they were attempting to play an awkward social situation in the best way possible.
BOX: Little Albert
Watson and Rayner's study was conducted in a haphazard, barely controlled way. Some fear of stimuli was induced and did generalise, but not in the neat, consistent way that textbook authors have reported. Watson and Rayner banged a steel bar and claw hammer together behind 11-month-old Little Albert's back at the same time as they presented him with a white rat. This was done seven times, over two sessions, a week apart, after which Albert cried and attempted to avoid the white rat when presented with it.
Five days later, Albert showed a fearful response to the rat, a rabbit, a dog, a sealskin coat and what's described as a 'negative response' to a Santa Claus mask and to Watson's hair, as well as a mild response to cotton. However, he played happily with the hair of Watson's assistants. In short, the infant had hardly shown a neat transfer of his fear to all things white and fluffy as is often reported.
After five more days Watson again conditioned Albert to fear the rat and this time also conditioned him to fear the rabbit and dog. Later that same day Albert barely reacted when presented with these animals in a different room – again showing how messy the real results were. Finally, 31 days later, Albert was tested again with many of these stimuli. He showed a fear response to the rat, mask, coat, rabbit and dog, yet he also initiated contact with the coat and rabbit.
BOX: The Hawthorne effect
The investigations into factory productivity at Hawthorne were never published in a peer-reviewed journal, and the term 'Hawthorne effect' was in fact coined many years later by John French in 1953 in his chapter contribution to a book on research methods.
According to separate analyses of the Hawthorne studies by H.M. Parsons in 1974 and Edwin Gale in 2004, the idea of a 'Hawthorne effect' probably stems from experiments on the effect of such factors as lighting, ventilation, payment method and supervision, often at the same time, on the productivity of women working on telephone relays. For example, one study involved the female factory workers witnessing the lights being re-fitted with ostensibly superior bulbs, which were in fact identical, and those women then showing improved performance.
A key flaw in the studies, according to Chiesa and Hobbs, is that two of the five female workers were replaced between experimental conditions in a repeated measures design, obviously meaning that any observed effects could have been due to a change in personnel rather than anything more complicated.
BOX: What cognitive revolution?
Never mind that key studies in psychology are a little mythical, Sandy Hobbs believes there are in fact entire movements in our science's history that may have a whiff of fiction about them too. Test any psychologist on the history of psychology and they'll probably tell you that the first half of the 20th century was dominated by behaviourism, before the rise of computers inspired the cognitive revolution of the latter half of the century. But Hobbs says they're wrong on both counts. Citing the work of Alexander Lovie, who used mentions of the word 'attention' in psychology journals as a proxy for the status of the cognitive approach, Hobbs says there was only a tiny dip in articles dealing with attention in the 1930s and 40s, and that behaviourism never really dominated during that time.
'Behaviourists were studying animal cognition' he says, 'and psychoanalysis and gestalt psychology were also flourishing alongside.' On the other hand, there's no evidence that behaviourism died in the 1950s or that it isn't thriving today. 'The first Skinnerian journal was published in the 50s,' says Hobbs, 'and today there are 20 or 30 of them.'
'Many psychologists would say that cognitive psychology is the main approach,' Hobbs continues, 'but the existence of a flourishing comparative approach to psychology is a bit of an embarrassment to them because it means that we haven't established a Kuhnian [Thomas Kuhn was an eminent historian of science] "normal science" as you have with physics and chemistry. I think that's the attraction of the cognitive revolution as a myth. It's a way of dealing with uncomfortable facts about our subject.'
Learning from educational neuroscience
The shaping of us
Walking through snow to get to work


text:
SENATOR DIANNE FEINSTEIN
from Senator Dianne Feinstein held on August 29, 2017
A Conversation About America and the World
Senator Dianne Feinstein is one of the most accomplished women of our time, serving California in the U.S. Senate for nearly 25 years. During her tenure, she has served on numerous Senate committees and has pioneered many indelible legislative achievements. Before serving in the Senate, Dianne Feinstein was the first female president of the San Francisco Board of Supervisors and the first female mayor of San Francisco. She was elected to the U.S. Senate in 1992 with former U.S. Senator Barbara Boxer (D-CA) in the Year of the Woman, eventually becoming the first woman to serve on the Senate Judiciary Committee, Intelligence Committee and Rules Committee. She has established a reputation as a bipartisan leader willing to work with both sides of the aisle to solve difficult problems.
As California's senior senator, she has focused her career on emphasizing national security, combatting crime, and protecting California's waters, deserts and forests. Join Senator Feinstein for a wide-ranging discussion on her career as senator, California's role on the national stage and current domestic and international challenges.
U.S. Senator (D-CA)
In Conversation with the Honorable Ellen Tauscher
Former Representative, California's 10th Congressional District; Former Undersecretary of State for Arms Control and International Security; Member, Commonwealth Club's Board of Governors


Originating in the 1920s, The Occult Digest is now reborn at the hands of Black Moon Publishing.
…it is our goal to bring this time-tested entity into the present day to give voice to the many writers, artists and poets representing the myriad facets of esoteric thought, practice, and expression.
I am proud to say that this edition also includes my interview with Sean Woodward, Grand Master for Great Britain & Ireland of the Ordo Templi Orientis Antiqua & La Couleuvre Noire. He is a contemporary esotericist, with over three and a half decades of dedicated magickal experience and seeks to create artistic portals and magickal machines of illumination and devotion to the Hoodoo and Les Vudu. You can find more about Sean HERE.
This week I celebrated my birthday, except it was an exceptionally bittersweet day … The afternoon before my birthday I found out that the man I consider and love as my childhood father and spiritual father was dying. The morning of my birthday, I was told he had died in the night.
Before now, I have loved, lost and grieved my adopted Navajo mother and a man I referred to as my "Spirit-Grandfather". Each of them taught me so much and allowed me to unfold as I needed to at the time. The relationships were not perfect …; these were multi-faceted, loving, poetic, challenging, supportive, joyous and in all we focused as much on the spiritual as the profane, in differing ways.
Sitting in a castle dungeon in Germany, writing an essay on the Holocaust, the sunlight streaming through the open door, when suddenly all went dark … a tall man stood in the doorway, like a shadow, the backlit sun obscuring his features in darkness. His booming voice filled the dungeon as he began, without any greeting, to recite poetry to me in German. This was the moment I met my Spirit-Grandfather.
Travelling through the New Mexican desert with my adopted mother, visiting Hopi First Mesa. The Hopi women staring suspiciously at the Native American and the white woman, wondering how the hell we fit together. Shimá, my mother, explains to them that I am her adopted daughter. The women smile and laugh and open their arms welcomingly. They feed us blue bread which is so fine that it breaks apart like ashes and floats off in the wind as I laugh.
Visiting my childhood father at the monastery where he was abbot. He hugs me hello and it's the best and safest hug I have every experienced. I cry. He sits me down with a bowl of tea. I am fascinated that the monks drink tea and coffee from big bowls. My father tells me he refuses to hear any confession from me, that I am a child and have committed no sin. Instead we pray and then he recites poetry to me. This time it's his turn to cry as he always does when he recites poetry. I hold his hand and we sit quietly before the Muse.
The memories are in my blood. They reside within me. May Ma'at's feather be on their tongues. May they pass into the Du'at. May their souls be elevated so they join the blessed Aakhu. I grieve the loss of them, yet I know they are not truly lost, merely dis-placed, a shift in time and place, multi-layered eternity. Like Isis re-membering Osiris, so my memories allow them to be both dead and alive.