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1 Heuristics
[A]t one point AM [Automatic Mathematician] had some notions of sets, set-operations, numbers, and simple arithmetic. One heuristic rule it knew said " If F is an interesting relation, then look at its inverse". This rule fired after AM had studied "multiplication" for a while. The r.h.s. of the rule then directed AM to define and study the relation "divisors-of" (e.g. divisors-of (12) {1,2,3,4,6,12}. Another heuristic rule that later fired said " If f is a relation from A into B, then it's worth examining those members of A which map into extremal members of B." In this case, f was matched to "divisors-of", A was "numbers", B was "sets of numbers", and an extremal member of B might be, e.g., a very small set of numbers. Thus this heuristic rule caused AM to define the set of numbers with no divisors, the set of numbers with only 1 divisor, with only 2 divisors, etc. One of these sets (the last [ sic] mentioned) turned out subsequently to be quite important; these numbers are of course the primes. (Lenat & Harris, 1978, p. 30)Extraordinarily rapid progress during the early stages of an attack on a new problem area is a rather common occurrence in AI research; it merely signifies that the test cases with which the system has been challenged are below the level of difficulty where combinatorial explosion of the number of pathways in the problem space sets in.... It is the goal of AI research to move that threshold higher and higher on the scale of problem complexity through the introduction of heuristics-heuristics to reduce the rate of growth of the solution tree, heuristics to guide the development of the tree so that it will be rich in pathways leading to satisfactory problem solutions, and heuristics to direct the search to the "best" of these pathways. (Gelernter, quoted in Barr & Feigenbaum, 1982, pp. 139-140)Historical dictionary of quotations in cognitive science > Heuristics
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2 retourner
retourner [ʀ(ə)tuʀne]➭ TABLE 1━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━1. transitive verba. ( = mettre dans l'autre sens) [+ caisse, seau] to turn upside down ; [+ matelas, carte, omelette] to turn overb. [+ terre] to turn overc. ( = mettre l'intérieur à l'extérieur) [+ parapluie, sac, vêtement] to turn inside out ; [+ col] to turnd. ( = orienter dans le sens opposé) [+ mot, phrase] to turn rounde. ( = renvoyer) [+ lettre, marchandise] to returnf. ( = bouleverser) [+ maison, pièce] to turn upside down ; [+ personne] to shake• il a tout retourné dans la maison pour retrouver ce livre he turned the whole house upside down to find that bookg. ( = tourner plusieurs fois) retourner une idée dans sa tête to turn an idea over in one's mind2. intransitive verba. ( = aller à nouveau) to return, to go back• retourner en Italie/à la mer to return or go back to Italy/to the seaside• retourner en arrière or sur ses pas to turn back• il retourne demain à son travail/à l'école he's going back to work/to school tomorrow4. reflexive verba. [personne couchée, automobiliste, véhicule] to turn over ; [bateau] to capsize• il doit se retourner dans sa tombe ! he must be turning in his grave!b. ( = tourner la tête) to turn round• tout le monde se retournait sur lui or sur son passage everyone turned round as he went byc. [situation] to be turned round• se retourner contre qn [personne] to turn against sb ; [acte, situation] to backfire on sb ; ( = poursuivre en justice) to take court action against sb━━━━━━━━━━━━━━━━━* * *ʀ(ə)tuʀne
1.
verbe transitif (+ v avoir)1) ( changer de côté) to turn [something] over [seau, steak]; to turn [matelas]2) ( mettre à l'envers) to turn [something] inside out [vêtement, sac]3) ( tourner à plusieurs reprises) to turn over [terre]; to toss [salade, foin]retourner une idée dans sa tête — fig to turn an idea over in one's mind
4) ( changer d'orientation) to return [compliment, critique]5) ( bouleverser) [personne] to turn [something] upside down [maison]; [nouvelle, spectacle] to shake [personne]je suis encore tout retourné — (colloq) I'm still quite shaken
6) ( renvoyer) to send [something] back, to return [colis, lettre]
2.
verbe intransitif (+ v être) to go back (à to), to return (à to)
3.
se retourner verbe pronominal1) ( tourner la tête) to turn aroundpartir sans se retourner — lit, fig to leave without a backward glance
elle est tellement grande que tout le monde se retourne sur son passage — she's so tall that everybody turns to look as she goes past
2) to turn over3) ( s'organiser) to get organized4) ( prendre un tour inverse)se retourner contre quelqu'un — [personne, animal] to turn against somebody; [situation, agissements] to backfire on somebody
5) ( se tordre)6) ( repartir)
4.
verbe impersonnel••retourner quelqu'un comme une crêpe (colloq) or un gant — (colloq) to make somebody change their mind completely
* * *ʀ(ə)tuʀne1. vt1) (= changer de côté) [matelas, crêpe] to turn overElle a retourné la crêpe. — She turned the pancake over.
2) (= renverser) to turn upside downIl a retourné la poubelle. — He turned the bin upside down.
3) [sac, vêtement] to turn inside outretourner sa veste fig — to change sides, to go over to the other side
4) [terre, sol, foin] to turn over5) [arme] to turn roundretourner une arme contre soi — to turn a weapon against o.s.
6) [argument] to turn round7) (= émouvoir) [personne] to shake8) (= renvoyer)2. vi(= aller, revenir)retourner à [endroit] — to go back to, to return to, [état, activité] to return to, to go back to
3. vb impers(= s'agir)* * *retourner verb table: aimerA vtr (+ v avoir)1 ( changer de côté) to turn [sth] over [seau, caisse, steak, poisson]; to turn [matelas]; retourner une carte à jouer ( figure visible) to turn up a playing card; ( figure pas visible) to put a playing card face down; retourner un tableau contre le mur to turn a painting to the wall;2 ( mettre à l'envers) to turn [sth] inside out [vêtement, sac]; Cout to turn [vêtement, coussin, col]; un coup de vent a retourné son parapluie a gust of wind turned his umbrella inside out; il a retourné ses poches à la recherche de quelques sous he turned his pockets inside out looking for some change;3 ( tourner à plusieurs reprises) to turn over [terre]; to toss [salade, foin]; retourner une idée or pensée dans sa tête to turn an idea ou a thought over in one's mind;4 ( changer d'orientation) to return [compliment, critique]; retourner la situation to reverse the situation; elle a retourné le pistolet contre elle-même she then turned the gun on herself; si tu retournes l'argument contre lui if you turn his own argument against him;5 ( bouleverser) [personne] to turn [sth] upside down [maison, pièce]; [nouvelle, spectacle] to shake [personne]; elle a retourné toute la maison pour retrouver la facture she turned the house upside down trying to find the bill; je suis encore tout retourné○ I'm still quite shaken;6 ( renvoyer) to send [sth] back, to return [colis, lettre, marchandise].B vi (+ v être)1 ( aller à nouveau) to go back, to return (à to); retourner dans son village natal to return to the village where one was born; retourner chez le dentiste/médecin pour une nouvelle visite to go back to the dentist's/doctor's for another visit; retourner à l'école/au bureau to go back to school/to the office; je n'y suis jamais retourné depuis I've never been back ou never returned since;2 ( à un état antérieur) to go back (à to), to return (à to); animal qui est retourné à l'état sauvage animal that has gone back ou returned to its wild state; retourner à ses premières amours liter to return to one's first love; il est retourné à son laboratoire et à ses expériences he went back to his laboratory and to his experiments; les biens retournent à leur légitime possesseur the property reverts to its rightful owner.C se retourner vpr1 ( tourner la tête) to turn around, to turn round GB; je l'ai appelée et elle s'est retournée I called her and she turned around; partir sans se retourner lit, fig to leave without once looking back; elle est tellement grande que tout le monde se retourne sur son passage she's so tall that everybody turns to look as she goes past;2 ( changer de position) [personne couchée] to turn over; [véhicule, automobiliste] to turn over, to overturn; se retourner sur le dos/ventre to turn over onto one's back/stomach; il n'a pas arrêté de se retourner (dans son lit) pendant toute la nuit he kept tossing and turning all night long; la voiture s'est retournée dans un fossé the car overturned into a ditch;3 ( s'organiser) to get organized; ça lui laissera le temps de se retourner it'll give her time to sort things out ou to get organized;4 ( prendre un tour inverse) se retourner contre qn [personne, animal] to turn against sb; [situation, agissements] to backfire on sb; se retourner contre ses alliés to turn on one's allies; ses arguments se sont retournés contre lui his arguments backfired on him;5 ( se tordre) elle s'est retourné le doigt/un ongle she bent back her finger/a nail;D v impers j'aimerais savoir de quoi il retourne I'd like to know what's going on.retourner qn comme une crêpe○ or un gant○ to make sb change their mind completely.[rəturne] verbe transitif (auxiliaire avoir)1. [orienter dans le sens contraire] to turn round ou around (separable)retourner une arme contre ou sur quelqu'un to turn a weapon on somebodyje lui ai retourné son ou le compliment I returned the compliment2. [renvoyer - colis, lettre] to send back (separable)3. [mettre à l'envers - literie] to turn round ou around ; [ - carte à jouer] to turn up (separable) ; [ - champ, paille] to turn over (separable) ; [ - verre] to turn upside down ; [ - grillade] to turn over (separable) ; [ - gant, poche] to turn inside out4. [mélanger - salade] to toss5. [fouiller - maison, pièce] to turn upside down6. [examiner - pensée]7. (familier) [émouvoir]————————[rəturne] verbe intransitif (auxiliaire être)si tu étais à ma place, tu retournerais le voir? if you were me, would you (ever) go and see him again?je retournai la voir une dernière fois I paid her one ou my last visitretourner à sa place [sur son siège] to go back to one's seat————————[rəturne] verbe impersonnelpeut-on savoir de quoi il retourne? what is it all about?, what exactly is going on?————————retourner à verbe plus préposition————————se retourner verbe pronominal intransitif1. [tourner la tête] to turn round2. [se mettre sur l'autre face] to turn overse retourner sur le dos/ventre to turn over on one's back/stomach3. [se renverser - auto, tracteur] to overturn, to turn over4. [réagir] to sort things outa. [de décider] they won't give me time to make a decisionb. [de me reprendre] they won't give me time to sort things outle lendemain, la situation s'était retournée the following day, the situation had changed beyond recognition6. [déplacement]s'en retourner [partir]a. to depart, to leaveb. [rentrer] to make one's way back————————se retourner verbe pronominal transitifse retourner un ongle/doigt to twist a nail/finger————————se retourner contre verbe pronominal plus préposition1. [agir contre]
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