المجموعة الشمسية

كواكب المجموعة الشمسية
الزهرة
إن كوكب الزهرة كان ولا يزال ألمع جرم سماوي بعد الشمس و القمر,ولعل هذا هو السبب في تسميته بنجمة الصباح تارة ونجمة المساء تارة أخرى,تتوفر الزهرة على غلاف جوي سميك جدا و كثيف,مما يجعل مشاهدة سطحها أمرا صعبا للغاية,و يتكون هذا الغلاف أساسا من الغاز الكربوني و حمض السولفيريك. و تعزى الحرارة اللاهبة على سطحها إلى مفعول البيت الزجاجي أو الاحتباس الحراري الناتج عن كثافة الغاز الكاربوني الذي يحيل هذا الكوكب الذي تغنى بجماله القدماء إلى جحيم لا يطاق.
الزهرة بالأرقام
القطر عند خط الاستواء:
12104 كلم
البعد المتوسط عن الشمس:
108.19 مليون كلم
السرعة المدارية المتوسطة:
53.03 كلم/الثانية
السنة بالتقويم الأرضي:
224.7 يوما أرضيا
اليوم بالتقويم الأرضي:
243.01 يوما أرضيا
الثقالة:
50 كلغ على الأرض=47 كلغ على الزهرة
درجات الحرارة المتوسطة:
465°
التوابع:
لا يوجد


عطارد

عطارد هو أقرب كواكب المجموعة الشمسية إلى الشمس, وتغطي قشرته السطحية الصخرية قلبا هائلا من الحديد, و المثير للانتباه في هذا الكوكب هو سطحه المليء بالفوهات التي خلفتها النيازك التي اصطدمت به على مر السنين. أما بالنسبة للغلاف الجوي, فهو جد ناد, ماعدا نسب قليلة من الهيدروجين و الهيليوم. أما درجات الحراة, فالعليا تسجل في الجانب المواجه للشمس, في حين أن الجانب المظلم أبرد بكثير, و يعود هذا الاختلاف إلى أمرين: أولهما بطء دورة عطارد حول محوره فهو يتمها في 59 يوما أرضيا, وثانيهما انعدام الغلاف الجوي أو بالأحرى ندرته.
عطارد بالأرقام
القطر عند خط الاستواء:
4878كلم
البعد المتوسط عن الشمس:
57.93مليون كلم
السرعة المدارية المتوسطة:
47.89 كلم/الثانية
السنة بالتقويم الأرضي:
87.97 يوما أرضيا
اليوم بالتقويم الأرضي:
58.65 يوما أرضيا
الثقالة:
50 كلغ على الأرض=19 كلغ على عطارد
درجات الحرارة المتوسطة:
-180°/430°
التوابع:
لا يوجد

كوكب الأرض

و يعرف أيضا باسم الكرة الأرضية، هو كوكب تعيش فيه كائنات حية و منها الإنسان، والكوكب الثالث بعدا عن الشمس في أكبر نظام شمسي، والجسم الكوكبي الوحيد في النظام الشمسي الذي يوجد به حياة، على الأقل المعروف إلى يومنا هذا، كوكب الأرض لَهُ قمر واحد، تشكّلَ قبل حوالي 4.5 بليون سنة مضت.
يطلق عليها بالإغريقية وتعتبر الأرض أكبر الكواكب الأرضية الأربعة في المجموعة الشمسية الداخلية . وهي الكوكب الوحيد الذي يظهر به كسوف الشمس. ولها قمر واحد وفوقها حياة وماء. وتعتبر أرضنا واحة الحياة حتي الآن حيث تعيش وحيدة في الكون المهجور. وحرارة الأرض ومناخها وجوها المحيط وغيرهم قد جعلتنا نعيش فوقها. وللأرض قمر واحد يطلق عليه لونا (Luna) . متوسط درجة حرارتها 15 درجة مئوية، أما جوها به أكسجين ونيتروجين وآرجون.
أبعاد الأرض ‏


مقارنة أحجام الكواكب فسه الذي يستغرقه دورانه حول الأرض , ولذلك فإن الجانب نفسه من القمر ( الجانب القريب ) , هو الذي الداخلية (من اليسار إلى اليمين): عطارد، الزهرة، الأرض، والمريخ
عالم عجيب
كوكب الأرض هو ثالث الكواكب بعدا عن الشمس , وهو أكبر الكواكب الصخرية وأشدها كثافة , والوحيد المعروف بإيوائه الحياة ورعايتها بنيته الداخلية , الصخرية والمعدنية , هي بنية نموذجية لكوكب صخري , أما القشرة فغير اعتيادية , إذ تتكون من صفائح منفصلة , يتحرك بعضها ببطء بالنسبة لبعضها الآخر , وتحصل الزلازل والنشاطات البركانية محاذاة الحدود التي تتصادم عندها هذه الصفائح يقوم الغلاف الجوي للأرض بدور غطاء واق , يوقف الأشعة الشمسية الضارة ويحول دون وصول الأحجار النيزكية إلى سطح الأرض إلى ذلك , يحتبس الغلاف الجوي كمية من الحرارة كافية لتحول دون حدوث درجات قصية من البرودة يغطي الماء حوالي 71 بالمئة من سطح الأرض , وهو لا يوجد بشكله السائل على سطح أي كوكب آخر للأرض تابع طبيعي واحد هو القمر , وهو كبير إلى درجة يمكن معها اعتبار الجرمين , الكوكب والتابع , بمثابة نظام ثنائي الكواكب .
القمر
القمر هو التابع الطبيعي الوحيد للأرض , وهو كبير نسبيا إذ يبلغ قطره 3470 كلم, أي أكثر بقليل من ربع قطر الأرض يستغرق دوران القمر حولي محوره 27,3 يوما , وهو الوقت نيواجهنا دائما وفي أية حال , فإن المقدار الذي نشاهده - والذي ندعوه الطور القمري- مرتبط بالمقدار المعرض لأشعة الشمس من الجانب القريب القمر جاف وقاحل وليس له غلاف جوي ولا مياه , وهو يتألف بشكل رئيسي من صخر صلب , رغم أن لبه قد يكون محتويا على حديد أو صخورا منصهرة سطح القمر كثير الغبار ويشتمل على هضبات مغطاة بالفوّهات الناشئة عن صدمات الأحجار النيزكية , ومنخفضات تمتلئ فوهاتها المتسعة باللأبة ( الحمم البركانية ) المتصلبة , مشكلة مناطق داكنة تسمى اصطلاحا - البحار توجد البحار بشكل رئيسي على الجانب القريب من القمر الذي يتميز عن الجانب البعيد غير المرئي بقشرة أرق يحيط بالعديد من الفوهات سلاسل جبلية هي بمثابة جدران لها , ويصل ارتفاع بعضها إلى آلاف الأمتار .
الأرض في القرآن
ورد ذكر كلمة ( الأرض ) مفردة ومجتمعة مع مشتقاتها في القرآن ( 461 ) مرة . وجاءت الكلمة للدلالة على الأرض جميعها في بعض المواضع , وللدلالة على جزء منها في مواضع أخرى واقترن خبر خلق السماوات والأرض في مواضع كثيرة . ولعل أبرز الآيات التي وردت في تفصيل خلق الأرض وما عليها هي الآيات من سوره فصلت وفيها تقرأ ( قل أئنكم لتكفرون بالذي خلق الأرض في يومين وتجعلون له أندادا ذلك رب العالمين * وجعل فيها رواسي من فوقها وبارك فيها وقدر أقواتها في أربعة أيام سوآء للسائلين) فصلت : 9 - 10 عمر الأرض في حسابات الفلكية , وبموجب المكتشفات الجيولوجية يقدر بأربعة آلاف وخمسمائة مليون سنة كما ذكر القرآن الكريم أن السماوات والأرض كانتا وحدة واحدة ( رتقا ) ثم ( فتقنا ) : ( أولــم ير الذين كفروا أن السماوات والأرض كانتا رتقا ففتقناهما وجعلنا من الماء كل شيء حي أفلا يؤمنون ) الأنبياء : 30 وهذه حقيقة علمية صحيحة إذ كان الأرض جزءا من الغيمة الدّعيّة التي تكوّن منها النظام الشمسي . كما تحدث القرآن عن صفات أخرى كثيرة للأرض وما عليها , فورد أن الله ( طحاها ) وأورد الله ( دحاها ) , وبرغم ما يرد في التفاسير من أن هذه المفردات تعني ( بسطها ) إلا أننا نرى أن فيها دلالات أعمق من ذلك كلها تشير إلى كرويتها وحركتها حول نفسها . أما فيما يخص حركة الأرض حول الشمس فإن القرآن لم يورد ذلك صراحة . . بل أشار إليه إشارة , إذ نقرأ في سورة الكهف : ( وترى الجبال تحسبها جامدة وهي تمر مر السحاب صنع الله الذي أتقن كل شيء إنه خبير بما تفعلون ) النمـــل : 88 فها هنا إشارة أخرى إلى حركة الأرض . والأرجح أنها الحركة في الفضاء لأن قياس الحركة كان إلى شيء سماويّ يعلو الأرض وينفصل عنها . وهو السحاب .. يقول الله تعالى : ( وألقى في الأرض رواسي أن تميد بكم ) النحــل : 15 وقال تعالى : ( وجعلنا في الأرض رواسي أن تميد بهم ) الأنبياء : 31 وذكر الله تعالى في سورة لقمان أية : 10 مثل ما ذكر في سورة النحل أية 15 ولو تأملنا معنى الميــد في اللغة لوجدنا ما يلي : الميــد : التحرك .. وأصابه ميد , أي دوار من ركوب البحر . هنا نلحظ في الآيات الواردة أعلاه أن الله تعالى استعمل كلمة ( تميـد ) ولم يستعمل كلمة ( تميـل ) .. فلو كانت الأرض كانت الأرض مستوية طافية في الفضاء أو على سطح الماء مثلما تصورها الأقدمون لكان استعمال لفظة ( تميل ) أصح من استعمال لفظة ( تميد ) .. إلا أن وجود الحركة ( وهو دوران الأرض حول نفسها ) يجعل الميل الحاصل ميلا متحركا على قوس . ولو كانت الأرض سطحا متعرّجا كما هي عليه دون أن يكون لهذا التعرج الممثل ببروز الجبال حساب دقيق في توزيع الكتل لأدى ذلك إلى ( ميد) في حركة الأرض أثناء دورانها حول نفسها . أي كانت حركة الدوران تتمّ حول دائرة يتحرك على محيطها محور الأرض , فلا يكون عندئذ محور الدوران ثابتا .. ومثل هذه الحركة تؤدي بماعلى الأرض إلى الدوار , كما يحصل تماما لراكب البحر . إذن فإن للرواسي ( الجبال ) المتوزعة على سطح الأرض وفق حساب دقيق يراعي توزيع الكتل بين اليابسة والماء أهمية كبيرة في استقرار حركة الأرض حول محور ثابت أثناء دورانها .. ولو ذلك لحصل دوار للناس من جراء الحركة إن الأرض بدورانها حول الشمس تتبعها في حركتها أيضا , ولما كانت الشمس تتحرك حركتين داخل المجرّة أحداهما دوارنيّة والأخرى محليّة , فإن الأرض تتحرك معها أيضا .. كوكب الأرض هو ثالث الكواكب بعدا عن الشمس , وهو أكبر الكواكب الصخرية وأشدها كثافة , والوحيد المعروف بإيوائه الحياة ورعايتها بنيته الداخلية , الصخرية والمعدنية , هي بنية نموذجية لكوكب صخري , أما القشرة فغير اعتيادية , إذ تتكون من صفائح منفصلة , يتحرك بعضها ببطء بالنسبة لبعضها الآخر , وتحصل الزلازل والنشاطات البركانية محاذاة الحدود التي تتصادم عندها هذه الصفائح يقوم الغلاف الجوي للأرض بدور غطاء واق , يوقف الأشعة الشمسية الضارة ويحول دون وصول الأحجار النيزكية إلى سطح الأرض إلى ذلك , يحتبس الغلاف الجوي كمية من الحرارة كافية لتحول دون حدوث درجات قصية من البرودة يغطي الماء حوالي 70 بالمئة من سطح الأرض , وهو لا يوجد بشكله السائل على سطح أي كوكب آخر للأرض تابع طبيعي واحد هو القمر , وهو كبير إلى درجة يمكن معها اعتبار الجرمين , الكوكب والتابع , بمثابة نظام ثنائي الكواكب القمر القمر هو التابع الطبيعي الوحيد للأرض , وهو كبير نسبيا إذ يبلغ قطره 3470 كلم, أي أكثر بقليل من ربع قطر الأرض يستغرق دوران القمر حولي محوره 27,3 يوما , وهو الوقت نفسه الذي يستغرقه دورانه حول الأرض , ولذلك فإن الجانب نفسه من القمر ( الجانب القريب ) , هو الذي يواجهنا دائما وفي أية حال , فإن المقدار الذي نشاهده - والذي ندعوه الطور القمري- مرتبط بالمقدار المعرض لأشعة الشمس من الجانب القريب القمر جاف وقاحل وليس له غلاف جوي ولا مياه , وهو يتألف بشكل رئيسي من صخر صلب , رغم أن لبه قد يكون محتويا على حديد أو صخورا منصهرة سطح القمر كثير الغبار ويشتمل على هضبات مغطاة بالفوّهات الناشئة عن صدمات الأحجار النيزكية , ومنخفضات تمتلئ فوهاتها المتسعة باللأبة ( الحمم البركانية ) المتصلبة , مشكلة مناطق داكنة تسمى اصطلاحا - البحار توجد البحار بشكل رئيسي على الجانب القريب من القمر الذي يتميز عن الجانب البعيد غير المرئي بقشرة أرق يحيط بالعديد من الفوهات سلاسل جبلية هي بمثابة جدران لها , ويصل ارتفاع بعضها إلى آلاف الأمتار
المدار و الدوران
الأرض تدور حول نفسها من الغرب إلى الشرق
خطر الانقراض
قال تقرير صادر عن الأمم المتحدة معني بوضع البيئة في العالم إن الكرة الأرضية تتجه نحو كارثة ما لم تُتَخذ إجراءات عاجلة. وأضاف التقرير الذي شارك في إعداده مئات العلماء من دول مختلفة من العالم أن استمرار الحياة البشرية على ظهر كوكب الأرض يمكن أن يكون أمرا مشكوكا فيه في حال واصل البشر استنزاف الموارد البيئية. وتابع التقرير أن العالم يحتاج إلى اتخاذ إجراءات عاجلة للتصدي لمشكلات من قبيل ارتفاع درجة حرارة الأرض والتنمية غير المستديمة وانقراض بعض الأنواع الحيوانية والنباتية. ويُذكر أن 30% من احتياطي السمك في العالم تعرض للانهيار. وأضاف التقرير أن مليار شخص في العالم النامي معرضون لخطر الإصابة بأمراض بسيطة نسبيا مثل الأمراض التي تحملها المياه، علما أنها كانت قد عولجت في مناطق أخرى من العالم.
ومن جهة أخرى، حذر تقرير آخر صادر عن الجمعية الدولية للحيوانات الثديية من أن نحو ثلث الحيوانات الثديية في العالم معرضة لخطر الانقراض بسبب تدمير المواطن الطبيعية التي تعيش فيها. وأضاف التقرير أن العديد من أنواع القرود وثدييات أخرى تُضطر إلى النزوح عن مواطنها الطبيعية في الغابات حيث تعيش أو تتعرض للقتل إما لاستهلاك لحومها أو لصنع الأدوية منها. ومن المقرر مناقشة أعضاء الجمعية الدولية للحيوانات الثديية نتائج التقرير في جزيرة هاينان الصينية.
وركز التقرير على مصير 25 نوعا من الثدييات والتي تُعتبر الأكثر عرضة لخطر الانقراض بسبب مجموعة من المشكلات الملحة. ويقول المشاركون في إعداد التقرير إن ما تبقى من الأنواع الأكثر عرضة لخطر الانقراض يمكن جمعها كلها في ملعب واحد لكرة القدم. وأبرز التقرير المخاوف الناجمة عن مصير القرود التي تعيش في جزيرة هاينان الصينية وتلك التي تستوطن ساحل العاج إذ أوضح أنه لم يتبق منها في الغابات سوى أعداد محدودة جدا. وأضاف التقرير أن آسيا معرضة أكثر من أي قارة أخرى في العالم لخطر انقراض بعض أنواع القرود منها حيث تتعرض الغابات الاستوائية فيها للتدمير في ظل صيد القرود أو بيعها كحيوانات أليفة. وذهب التقرير أيضا إلى أن التغير المناخي يساهم في جعل بعض أنواع القرود أكثر عرضة لخطر الانقراض.
وحذر العلماء على مدى عقود من الزمن من التهديد المتنامي الذي يشكله النشاط البشري على مصير بعض الأنواع الحيوانية في مناطق مختلفة من العالم. غير أن هذا التقرير يوصي بإيلاء اهتمام خاص لبعض الثدييات مثل أنواع معينة من القرود لأنها أقرب الكائنات الحيوانية إلى الإنسان.


زحـل

إن كوكب زحل أجمل الأجرام السماوية على الإطلاق, و ما هو في الواقع إلا فلكة عملاقة من الغاز ذات القلب المعدني المحاط بالهيدروجين و الهليوم. و حلقاته الرائعة المحيرة ما هي إلا ملايين من الصخور الجليدية التي انتظمت حوله في مدار ساحر. و يمكن ملاحظة ثلاث منها بسهولة بواسطة التلسكوب, و الرابعة كذلك تمت مشاهدتها أرضيا, إلا أن المعاينة عن قرب تبين أنها مكونة من الآلاف من الحلقات الصغيرة. ربما تكون هذه الحلقات بقايا قمر كان تابعا لزحل و انفجر فيما مضى أو لم يتم تشكله أصلا.إلا أن تاريخها حافل, فقديما, ظنها بعض المراقبين طيفا, وهناك من خالها قمرا, بل وصل الخيال بالبعض إلى تصورها كوكبا توأما لزحل.
زحل بالأرقام
القطر عند خط الاستواء:
120660 كلم
البعد المتوسط عن الشمس:
مليون كلم1425.84
السرعة المدارية المتوسطة:
9.64 كلم/الثانية
السنة بالتقويم الأرضي:
29.46 سنة أرضية
اليوم بالتقويم الأرضي:
10.2ساعة
الثقالة:
50 كلغ على الأرض=47 كلغ على زحل
درجات الحرارة المتوسطة:
-180°
التوابع:
لا تقل عن 21


المريخ
كوكب المريخ يتميز بلونه الأحمر ، وتتراوح درجة حرارته ما بين 300 درجة حرارة مطلقة و145 درجة حرارة مطلقة ، كما أن طول اليوم عليه قريب من طول اليوم على كوكبنا الأرض ، ويتم المريخ دورته حول الشمس في عامين تقريبا ، وكتلته تساوي عشر كتلة الأرض ، إلا أن قطره يساوي نصف قطر الأرض ودرجة الحرارة العالية للمريخ تجعلنا نعتقد أن هناك حياة عليه ، وإن كانت درجة البرودة تصل إلى حوالي 130 تحت الصفر. ونتيجة لصغر المريخ فإن له غلافا جويا رقيقا تجعل درجة عاكسيته أقل مما هو على الأرض ، لذا هو أقل لمعانا من الزهرة .
الخواص العامة للمريخ
المحور الكبير
1,524 وحدة فلكية
أقرب مسافة
1,381 وحدة فلكية
أبعد مسافة
1,667 وحدة فلكية
مقدار الاستطالة
0,093
السنة
1,881 سنة
ميل المدار
درجة واحدة و51 دقيقة
اليوم
24س 37ق 22,6ث
ميل المحورين
23 درجة و59 دقيقة
القطر
0,531 قطر أرضي
الكتلة
0,107 كتلة أرضية
الكثافة
3,96 جم/سم مكعب
قوة الجاذبية
0,38 جاذبية أرضية
سرعة الهروب
5كم/ث
درجة الحرارة
300 - 145 (K)
العاكسية
0,15
عدد الأقمار
2


المشتري
يعد المشتري أضخم كواكب المجموعة الشمسية على الإطلاق, وكتلته وحده تساوي ثلاثة أضعاف كتلة كل الكواكب الأخرى مجتمعة, يتوفر المشتري على قلب صخري صغير نسبيا محاط بطبقة من الهيدروجين السائل الذي يتصرف كالمعدن نتيجة للضغط الهائل الذي يتلقاه,إضافة إلى طبقة أخرى من الهيدروجين و الهليوم الغازيين, و سحب مكونة من كريستالات الأمونياك و الميثان المتجمد و التي تشكل أشرطة حمراء و صفراء تحيط بالكوكب. و من أهم المعالم المميزة للمشتري, بقعته الحمراء الشهيرة والتي ربما تكون عاصفة من الغاز لا تهدأ على سطحه.
المشتري بالأرقام
القطر عند خط الاستواء:
142800كلم
البعد المتوسط عن الشمس:
778.26مليون كلم
السرعة المدارية المتوسطة:
13.06كلم/الثانية
السنة بالتقويم الأرضي:
11.86سنة أرضية
اليوم بالتقويم الأرضي:
9.8ساعات
الثقالة:
50كلغ على الأرض=117كلغ على المشتري
درجات الحرارة المتوسطة:
150-مئوية
التوابع:
لا يقل عن16


نبتون
يعد نبتون أبعد الكواكب الكبيرة عن الشمس, وهو ذو قلب صخري صغير محاط بمحيط من الماء, الأمونياك و الميثان المجمد. غلافه الجوي مكون من الهيدروجين,الهليوم والميثان, هذا الغاز الذي يعطي الكوكب لونه الأزرق المميز.
نبتون بالأرقام
القطر عند خط الاستواء:
49500 كلم
البعد المتوسط عن الشمس:
4496.38 مليون كلم
السرعة المدارية المتوسطة:
5.42 كلم/الساعة
السنة بالتقويم الأرضي:
164.79 سنة أرضية
اليوم بالتقويم الأرضي:
16.11 ساعة
الثقالة:
50 كلغ على الأرض=57 كلغ على نبتون
درجات الحرارة المتوسطة:
-214°
التوابع:
8

المذنبات
المذنبات هي كتل كبيرة من الجليد و الصخور التي تؤرخ لتكون النظام الشمسي. و هي تحوم حول الشمس في مدارات إهلليجية جد مستطيلة, وعندما تقترب منها, فإنها تتأثر بحرارتها فتنصهر محررة بذلك سيلا من الغازات تشكل ذيل المذنب, لذلك نجد هذا الأخير يتجه دائما معاكسا الشمس. و قد يحدث أن تخترق بقايا المذنبات الغلاف الجوي الأرضي في شكل نيازك تحترق بمجرد ولوجها إليه. كما قد تحدث اصطدامات بينها أو بين بقاياها و الكواكب مثل ما حدث بين المشتري ومذنب شوميخير ليفي 9 عام 1994.و من أشهر المذنبات مذنب هالي الذي يدور حول الشمس مرة كل 76 سنة,و مذنب هال بوب الأكثر لمعانا في المشاهدة الأرضية,ومذنب هياكوتاك الذي بلغ أقرب نقطة له من الأرض في 25 مارس 1996.


الكويكبات
يتموضع حزام الكويكبات بين مداري المريخ والمشتري. وهي عبارة عن كتل من الصخر أو المعادن تؤرخ لتكون المجموعة الشمسية, و يسود اعتقاد بأنها بقايا كوكب انفجر لسبب ما, أو مكونات كوكب لم يتم تشكيله, المهم, بالنسبة لحجمها, فهو يختلف من واحدة لأخرى حيث يمكن أن يتعدى أحيانا 1000 كلم قطرا في حين لا يصل في أخرى سوى بضع مئات من الأمتار. كما أنها تختلف فيما بينها من حيث الشكل فإن كان بعضها دائريا, فإن أغلبها ذات شكل غير منتظم, و قد يحدث أحيانا أن تخترق إحداها الغلاف الجوي للأرض فتعرف حينها بالنيازك. إذن فهي أصلا غير مشتعلة, إنما احتكاكها بالغلاف الجوي للأرض هو الذي يؤدي إلا توهجها, و رغم أن الكثير منها يسقط في مناطق غير مأهولة أو يحترق قبل وصوله, إلا أن النيازك سبق لها و ان أحدثت كوارث و مآسي, إذ أنه من المرجح أن الديناصورات قد انقرضت بعد سقوط نيزك ضخم ومدمر على الأرض منذ ملايين السنين.
تمثل الصورة أعلاه ثلاث كويكبات وهي : ماثيلد الأكبر على اليسار , و كاسبرا الأوسط ثم إيدأ على اليمين. وقد أخذت الصورة عن قرب بواسطة المركبة الفضائية نير سنة 1997.

Natural Numbers

In mathematics, a natural number can mean either an element of the set {1, 2, 3, ...} (the positive integers) or an element of the set {0, 1, 2, 3, ...} (the non-negative integers). The latter is especially preferred in mathematical logic, set theory, and computer science.
Natural numbers have two main purposes: they can be used for counting ("there are 3 apples on the table"), and they can be used for ordering ("this is the 3rd largest city in the country").
Properties of the natural numbers related to divisibility, such as the distribution of prime numbers, are studied in number theory. Problems concerning counting, such as Ramsey theory, are studied in combinatorics
History of natural numbers and the status of zero
The natural numbers had their origins in the words used to count things, beginning with the number 1.
The first major advance in abstraction was the use of numerals to represent numbers. This allowed systems to be developed for recording large numbers. For example, the Babylonians developed a powerful place-value system based essentially on the numerals for 1 and 10. The ancient Egyptians had a system of numerals with distinct hieroglyphs for 1, 10, and all the powers of 10 up to one million. A stone carving from Karnak, dating from around 1500 BC and now at the Louvre in Paris, depicts 276 as 2 hundreds, 7 tens, and 6 ones; and similarly for the number 4,622.
A much later advance in abstraction was the development of the idea of zero as a number with its own numeral. A zero digit had been used in place-value notation as early as 700 BC by the Babylonians, but they omitted it when it would have been the last symbol in the number.[1] The Olmec and Maya civilization used zero as a separate number as early as 1st century BC, developed independently, but this usage did not spread beyond Mesoamerica. The concept as used in modern times originated with the Indian mathematician Brahmagupta in 628. Nevertheless, medieval computists (calculators of Easter), beginning with Dionysius Exiguus in 525, used zero as a number without using a Roman numeral to write it. Instead nullus, the Latin word for "nothing", was employed. The first systematic study of numbers as abstractions (that is, as abstract entities) is usually credited to the Greek philosophers Pythagoras and Archimedes. However, independent studies also occurred at around the same time in India, China, and Mesoamerica.
In the nineteenth century, a set-theoretical definition of natural numbers was developed. With this definition, it was convenient to include 0 (corresponding to the empty set) as a natural number. Including 0 is now the common convention among set theorists, logicians, and computer scientists. Many other mathematicians also include 0, although some have kept the older tradition and take 1 to be the first natural number. Sometimes the set of natural numbers with 0 included is called the set of whole numbers or counting numbers.

William Shakespeare (baptised 26 April 1564 – 23 April 1616) was an English poet and playwright, widely regarded as the greatest writer in the English language and the world's preeminent dramatist. He is often called England's national poet and the "Bard of Avon" (or simply "The Bard"). His surviving works consist of 38 plays 154 sonnets, two long narrative poems, and several other poems. His plays have been translated into every major living language and are performed more often than those of any other playwright. Shakespeare was born and raised in Stratford-upon-Avon. At the age of 18, he married Anne Hathaway, who bore him three children: Susanna, and twins Hamnet and Judith. Between 1585 and 1592, he began a successful career in London as an actor, writer, and part owner of a playing company called the Lord Chamberlain's Men, later known as the King's Men. He appears to have retired to Stratford around 1613, where he died three years later. Few records of Shakespeare's private life survive, and there has been considerable speculation about such matters as his physical appearance, sexuality, religious beliefs, and whether the works attributed to him were written by others. Shakespeare produced most of his known work between 1590 and 1613. His early plays were mainly comedies and histories, genres he raised to the peak of sophistication and artistry by the end of the sixteenth century. He then wrote mainly tragedies until about 1608, including Hamlet, King Lear, and Macbeth, considered some of the finest works in the English language. In his last phase, he wrote tragicomedies, also known as romances, and collaborated with other playwrights. Many of his plays were published in editions of varying quality and accuracy during his lifetime. In 1623, two of his former theatrical colleagues published the First Folio, a collected edition of his dramatic works that included all but two of the plays now recognised as Shakespeare's.
Shakespeare was a respected poet and playwright in his own day, but his reputation did not rise to its present heights until the nineteenth century. The Romantics, in particular, acclaimed Shakespeare's genius, and the Victorians hero-worshipped Shakespeare with a reverence that George Bernard Shaw called "bardolatry In the twentieth century, his work was repeatedly adopted and rediscovered by new movements in scholarship and performance. His plays remain highly popular today and are constantly studied, performed and reinterpreted in diverse cultural and political contexts throughout the world.
Life
Early life
William Shakespeare was the son of John Shakespeare, a successful glover and alderman originally from Snitterfield, and Mary Arden, the daughter of an affluent landowning farmer. He was born in Stratford-upon-Avon and baptised on 26 April 1564. His unknown birthday is traditionally observed on 23 April, St George's Day. This date, which can be traced back to an eighteenth-century scholar's mistake, has proved appealing because Shakespeare died on 23 April 1616. He was the third child of eight and the eldest surviving son. Although no attendance records for the period survive, most biographers agree that Shakespeare was educated at the King's New School in Stratford, a free school chartered in 1553, about a quarter of a mile from his home. Grammar schools varied in quality during the Elizabethan era, but the curriculum was dictated by law throughout England, and the school would have provided an intensive education in Latin grammar and the classicsJohn Shakespeare's house, believed to be Shakespeare's birthplace, in Stratford-upon-AvonAt the age of 18, Shakespeare married the 26-year-old Anne Hathaway. The consistory court of the Diocese of Worcester issued a marriage licence on 27 November 1582. Two of Hathaway's neighbours posted bonds the next day as surety that there were no impediments to the marriage The couple may have arranged the ceremony in some haste, since the Worcester chancellor allowed the marriage banns to be read once instead of the usual three times Anne's pregnancy could have been the reason for this. Six months after the marriage, she gave birth to a daughter, Susanna, who was baptised on 26 May 1583 Twins, son Hamnet and daughter Judith, followed almost two years later and were baptised on 2 February 1585. Hamnet died of unknown causes at the age of 11 and was buried on 11 August 1596. After the birth of the twins, there are few historical traces of Shakespeare until he is mentioned as part of the London theatre scene in 1592. Because of this gap, scholars refer to the years between 1585 and 1592 as Shakespeare's "lost years". Biographers attempting to account for this period have reported many apocryphal stories. Nicholas Rowe, Shakespeare’s first biographer, recounted a Stratford legend that Shakespeare fled the town for London to escape prosecution for deer poaching Another eighteenth-century story has Shakespeare starting his theatrical career minding the horses of theatre patrons in London. John Aubrey reported that Shakespeare had been a country schoolmaster. Some twentieth-century scholars have suggested that Shakespeare may have been employed as a schoolmaster by Alexander Hoghton of Lancashire, a Catholic landowner who named a certain "William Shakeshafte" in his will No evidence substantiates such stories other than hearsay collected after his death
London and theatrical career
It is not known exactly when Shakespeare began writing, but contemporary allusions and records of performances show that several of his plays were on the London stage by 1592. He was well enough known in London by then to be attacked in print by the playwright Robert Greene:...there is an upstart Crow, beautified with our feathers, that with his Tiger's heart wrapped in a Player's hide, supposes he is as well able to bombast out a blank verse as the best of you: and being an absolute Johannes factotum, is in his own conceit the only Shake-scene in a country. Scholars differ on the exact meaning of these words, but most agree that Greene is accusing Shakespeare of reaching above his rank in trying to match university-educated writers, such as Christopher Marlowe, Thomas Nashe and Greene himself. The italicised phrase parodying the line "Oh, tiger's heart wrapped in a woman's hide" from Shakespeare’s Henry VI, part 3, along with the pun "Shake-scene", identifies Shakespeare as Greene’s target. Greene’s attack is the first recorded mention of Shakespeare’s career in the theatre. Biographers suggest that his career may have begun any time from the mid-1580s to just before Greene’s remarks. From 1594, Shakespeare's plays were performed only by the Lord Chamberlain's Men, a company owned by a group of players, including Shakespeare, that soon became the leading playing company in London. After the death of Queen Elizabeth in 1603, the company was awarded a royal patent by the new king, James I, and changed its name to the King's Men. In 1599, a partnership of company members built their own theatre on the south bank of the Thames, which they called the Globe. In 1608, the partnership also took over the Blackfriars indoor theatre. Records of Shakespeare's property purchases and investments indicate that the company made him a wealthy man. In 1597, he bought the second-largest house in Stratford, New Place, and in 1605, he invested in a share of the parish tithes in Stratford. Some of Shakespeare's plays were published in quarto editions from 1594. By 1598, his name had become a selling point and began to appear on the title pages. Shakespeare continued to act in his own and other plays after his success as a playwright. The 1616 edition of Ben Jonson's Works names him on the cast lists for Every Man in His Humour (1598) and Sejanus, His Fall (1603). The absence of his name from the 1605 cast list for Jonson’s Volpone is taken by some scholars as a sign that his acting career was nearing its end. The First Folio of 1623, however, lists Shakespeare as one of "the Principal Actors in all these Plays", some of which were first staged after Volpone, although we cannot know for certain what roles he played. In 1610, John Davies of Hereford wrote that "good Will" played "kingly" roles. In 1709, Rowe passed down a tradition that Shakespeare played the ghost of Hamlet's father Later traditions maintain that he also played Adam in As You Like It and the Chorus in Henry V though scholars doubt the sources of the information. Shakespeare divided his time between London and Stratford during his career. In 1596, the year before he bought New Place as his family home in Stratford, Shakespeare was living in the parish of St. Helen's, Bishopsgate, north of the River Thames. He moved across the river to Southwark by 1599, the year his company constructed the Globe Theatre there. By 1604, he had moved north of the river again, to an area north of St Paul's Cathedral with many fine houses. There he rented rooms from a French Huguenot called Christopher Mountjoy, a maker of ladies' wigs and other headgear.
Later years and death
After 1606–1607, Shakespeare wrote fewer plays, and none are attributed to him after 1613. His last three plays were collaborations, probably with John Fletcher, who succeeded him as the house playwright for the King’s MenRowe was the first biographer to pass down the tradition that Shakespeare retired to Stratford some years before his death; but retirement from all work was uncommon at that time, and Shakespeare continued to visit London. In 1612 he was called as a witness in a court case concerning the marriage settlement of Mountjoy's daughter, Mary. In March 1613 he bought a gatehouse in the Blackfriars priory; and from November 1614 he was in London for several weeks with his son-in-law, John HallShakespeare died on 23 April 1616and was survived by his wife and two daughters. Susanna had married a physician, John Hall, in 1607, and Judith had married Thomas Quiney, a vintner, two months before Shakespeare’s death. In his will, Shakespeare left the bulk of his large estate to his elder daughter Susanna. The terms instructed that she pass it down intact to "the first son of her body". The Quineys had three children, all of whom died without marrying The Halls had one child, Elizabeth, who married twice but died without children in 1670, ending Shakespeare’s direct line Shakespeare's will scarcely mentions his wife, Anne, who was probably entitled to one third of his estate automatically. He did make a point, however, of leaving her "my second best bed", a bequest that has led to much speculation. Some scholars see the bequest as an insult to Anne, whereas others believe that the second-best bed would have been the matrimonial bed and therefore rich in significance. Shakespeare was buried in the chancel of the Holy Trinity Church two days after his death The stone slab covering his grave is inscribed with a curse against moving his bones:with a half-effigy of him in the act of writing. Its plaque compares him to Nestor, Socrates, and Virgil In 1623, in conjunction with the publication of the First Folio, the Droeshout engraving was published.Shakespeare has been commemorated in many statues and memorials around the world, including funeral monuments in Southwark Cathedral and Poet's Corner in Westminster Abbey.
Plays
Scholars have often noted four periods in Shakespeare's writing career. Until the mid-1590s, he wrote mainly comedies influenced by Roman and Italian models and history plays in the popular chronicle tradition. His second period began in about 1595 with the tragedy Romeo and Juliet and ended with the tragedy of Julius Caesar in 1599. During this time, he wrote what are considered his greatest comedies and histories. From about 1600 to about 1608, his "tragic period", Shakespeare wrote mostly tragedies, and from about 1608 to 1613, mainly tragicomedies, also called romances.The first recorded works of Shakespeare are Richard III and the three parts of Henry VI, written in the early 1590s during a vogue for historical drama. Shakespeare's plays are difficult to date, however, and studies of the texts suggest that Titus Andronicus, The Comedy of Errors, The Taming of the Shrew and Two Gentlemen of Verona may also belong to Shakespeare’s earliest period. His first histories, which draw heavily on the 1587 edition of Raphael Holinshed's Chronicles of England, Scotland, and Ireland, dramatise the destructive results of weak or corrupt rule and have been interpreted as a justification for the origins of the Tudor dynasty. Their composition was influenced by the works of other Elizabethan dramatists, especially Thomas Kyd and Christopher Marlowe, by the traditions of medieval drama, and by the plays of Seneca. The Comedy of Errors was also based on classical models, but no source for the The Taming of the Shrew has been found, though it is related to a separate play of the same name and may have derived from a folk story. Like Two Gentlemen of Verona, in which two friends appear to approve of rape, the Shrew's story of the taming of a woman's independent spirit by a man sometimes troubles modern critics and directors. Oberon, Titania and Puck with Fairies Dancing. By William Blake, c. 1786. Tate Britain.Shakespeare's early classical and Italianate comedies, containing tight double plots and precise comic sequences, give way in the mid-1590s to the romantic atmosphere of his greatest comedies. A Midsummer Night's Dream is a witty mixture of romance, fairy magic, and comic lowlife scenes Shakespeare's next comedy, the equally romantic The Merchant of Venice, contains a portrayal of the vengeful Jewish moneylender Shylock which reflected Elizabethan views but may appear derogatory to modern audiences. The wit and wordplay of Much Ado About Nothing, the charming rural setting of As You Like It, and the lively merrymaking of Twelfth Night complete Shakespeare's sequence of great comedies. After the lyrical Richard II, written almost entirely in verse, Shakespeare introduced prose comedy into the histories of the late 1590s, Henry IV, parts 1 and 2, and Henry V. His characters become more complex and tender as he switches deftly between comic and serious scenes, prose and poetry, and achieves the narrative variety of his mature work This period begins and ends with two tragedies: Romeo and Juliet, the famous romantic tragedy of sexually charged adolescence, love, and death; and Julius Caesar—based on Sir Thomas North's 1579 translation of Plutarch's Parallel Lives—which introduced a new kind of dramaAccording to Shakespearean scholar James Shapiro, in Julius Caesar "the various strands of politics, character, inwardness, contemporary events, even Shakespeare's own reflections on the act of writing, began to infuse each other"Shakespeare's so-called "tragic period" lasted from about 1600 to 1608, though he also wrote the so-called "problem plays" Measure for Measure, Troilus and Cressida, and All's Well That Ends Well during this time and had written tragedies before. Many critics believe that Shakespeare's greatest tragedies represent the peak of his art. The hero of the first, Hamlet, has probably been more discussed than any other Shakespearean character, especially for his famous soliloquy "To be or not to be; that is the question."[86] Unlike the introverted Hamlet, whose fatal flaw is hesitation, the heroes of the tragedies that followed, Othello and King Lear, are undone by hasty errors of judgement. The plots of Shakespeare's tragedies often hinge on such fatal errors or flaws, which overturn order and destroy the hero and those he loves.[88] In Othello, the villain Iago stokes Othello's sexual jealousy to the point where he murders the innocent wife who loves him.[89] In King Lear, the old king commits the tragic error of giving up his powers, initiating the events which lead to the murder of his daughter and the torture and blinding of the Earl of Gloucester. According to the critic Frank Kermode, "the play offers neither its good characters nor its audience any relief from its cruelty".[90] In Macbeth, the shortest and most compressed of Shakespeare's tragedies,[91] uncontrollable ambition incites Macbeth and his wife, Lady Macbeth, to murder the rightful king and usurp the throne, until their own guilt destroys them in turn.[92] In this play, Shakespeare adds a supernatural element to the tragic structure. His last major tragedies, Antony and Cleopatra and Coriolanus, contain some of Shakespeare's finest poetry and were considered his most successful tragedies by the poet and critic T. S. Eliot.[93]
In his final period, Shakespeare turned to romance or tragicomedy and completed three more major plays: Cymbeline, The Winter's Tale and The Tempest, as well as the collaboration, Pericles, Prince of Tyre. Less bleak than the tragedies, these four plays are graver in tone than the comedies of the 1590s, but they end with reconciliation and the forgiveness of potentially tragic errors.[94] Some commentators have seen this change in mood as evidence of a more serene view of life on Shakespeare's part, but it may merely reflect the theatrical fashion of the day.[95] Shakespeare collaborated on two further surviving plays, Henry VIII and The Two Noble Kinsmen, probably with John Fletcher.[96]
Performances
It is not clear for which companies Shakespeare wrote his early plays. The title page of the 1594 edition of Titus Andronicus reveals that the play had been acted by three different troupes.[97] After the plagues of 1592–3, Shakespeare's plays were performed by his own company at The Theatre and the Curtain in Shoreditch, north of the Thames.[98] Londoners flocked there to see the first part of Henry IV, Leonard Digges recording, "Let but Falstaff come, Hal, Poins, the rest...and you scarce shall have a room".[99] When the company found themselves in dispute with their landlord, they pulled The Theatre down and used the timbers to construct the Globe Theatre, the first playhouse built by actors for actors, on the south bank of the Thames at Southwark.[100] The Globe opened in autumn 1599, with Julius Caesar one of the first plays staged. Most of Shakespeare's greatest post-1599 plays were written for the Globe, including Hamlet, Othello and King Lear.[101]After the Lord Chamberlain's Men were renamed the King's Men in 1603, they entered a special relationship with the new King James. Although the performance records are patchy, the King's Men performed seven of Shakespeare's plays at court between 1 November 1604 and 31 October 1605, including two performances of The Merchant of Venice.[102] After 1608, they performed at the indoor Blackfriars Theatre during the winter and the Globe during the summer.[103] The indoor setting, combined with the Jacobean fashion for lavishly staged masques, allowed Shakespeare to introduce more elaborate stage devices. In Cymbeline, for example, Jupiter descends "in thunder and lightning, sitting upon an eagle: he throws a thunderbolt. The ghosts fall on their knees."[104]The actors in Shakespeare's company included the famous Richard Burbage, William Kempe, Henry Condell and John Heminges. Burbage played the leading role in the first performances of many of Shakespeare's plays, including Richard III, Hamlet, Othello, and King Lear.[105] The popular comic actor Will Kempe played the servant Peter in Romeo and Juliet and Dogberry in Much Ado About Nothing, among other characters.[106] He was replaced around the turn of the sixteenth century by Robert Armin, who played roles such as Touchstone in As You Like It and the fool in King Lear.[107] In 1613, Sir Henry Wotton recorded that Henry VIII "was set forth with many extraordinary circumstances of pomp and ceremony".[108] On 29 June, however, a cannon set fire to the thatch of the Globe and burned the theatre to the ground, an event which pinpoints the date of a Shakespeare play with rare precision.[108]
Textual sources.
In 1623, John Heminges and Henry Condell, two of Shakespeare's friends from the King's Men, published the First Folio, a collected edition of Shakespeare's plays. It contained 36 texts, including 18 printed for the first time.[109] Many of the plays had already appeared in quarto versions—flimsy books made from sheets of paper folded twice to make four leaves.[110] No evidence suggests that Shakespeare approved these editions, which the First Folio describes as "stol'n and surreptitious copies".[111] Alfred Pollard termed some of them "bad quartos" because of their adapted, paraphrased or garbled texts, which may in places have been reconstructed from memory.[112] Where several versions of a play survive, each differs from the other. The differences may stem from copying or printing errors, from notes by actors or audience members, or from Shakespeare's own papers.[113] In some cases, for example Hamlet, Troilus and Cressida and Othello, Shakespeare could have revised texts between the quarto and folio editions. The folio version of King Lear is so different from the 1608 quarto that the Oxford Shakespeare prints them both, since they cannot be conflated without confusion.[114]
Poems
In 1593 and 1594, when the theatres were closed because of plague, Shakespeare published two narrative poems on erotic themes, Venus and Adonis and The Rape of Lucrece. He dedicated them to Henry Wriothesley, earl of Southampton. In Venus and Adonis, an innocent Adonis rejects the sexual advances of Venus; while in The Rape of Lucrece, the virtuous wife Lucrece is raped by the lustful Tarquin.[115] Influenced by Ovid's Metamorphoses,[116] the poems show the guilt and moral confusion that result from uncontrolled lust.[117] Both proved popular and were often reprinted during Shakespeare's lifetime. A third narrative poem, A Lover's Complaint, in which a young woman laments her seduction by a persuasive suitor, was printed in the first edition of the Sonnets in 1609. Most scholars now accept that Shakespeare wrote A Lover's Complaint. Critics consider that its fine qualities are marred by leaden effects.[118] The Phoenix and the Turtle, printed in Robert Chester's 1601 Love's Martyr, mourns the deaths of the legendary phoenix and his lover, the faithful turtle dove. In 1599, two early drafts of sonnets 138 and 144 appeared in The Passionate Pilgrim, published under Shakespeare's name but without his permission.[119]
Sonnets
Published in 1609, the Sonnets were the last of Shakespeare's non-dramatic works to be printed. Scholars are not certain when each of the 154 sonnets was composed, but evidence suggests that Shakespeare wrote sonnets throughout his career for a private readership.[121] Even before the two unauthorised sonnets appeared in The Passionate Pilgrim in 1599, Francis Meres had referred in 1598 to Shakespeare's "sugred Sonnets among his private friends".[122] Few analysts believe that the published collection follows Shakespeare's intended sequence.[123] He seems to have planned two contrasting series: one about uncontrollable lust for a married woman of dark complexion (the "dark lady"), and one about conflicted love for a fair young man (the "fair youth"). It remains unclear if these figures represent real individuals, or if the authorial "I" who addresses them represents Shakespeare himself, though Wordsworth believed that with the sonnets "Shakespeare unlocked his heart".[124] The 1609 edition was dedicated to a "Mr. W.H.", credited as "the only begetter" of the poems. It is not known whether this was written by Shakespeare himself or by the publisher, Thomas Thorpe, whose initials appear at the foot of the dedication page; nor is it known who Mr. W.H. was, despite numerous theories, or whether Shakespeare even authorised the publication.[125] Critics praise the Sonnets as a profound meditation on the nature of love, sexual passion, procreation, death, and time.[126]
Style
Shakespeare's first plays were written in the conventional style of the day. He wrote them in a stylised language that does not always spring naturally from the needs of the characters or the drama.[127] The poetry depends on extended, sometimes elaborate metaphors and conceits, and the language is often rhetorical—written for actors to declaim rather than speak. The grand speeches in Titus Andronicus, in the view of some critics, often hold up the action, for example; and the verse in Two Gentlemen of Verona has been described as stilted.[128]Soon, however, Shakespeare began to adapt the traditional styles to his own purposes. The opening soliloquy of Richard III has its roots in the self-declaration of Vice in medieval drama. At the same time, Richard’s vivid self-awareness looks forward to the soliloquies of Shakespeare's mature plays.[129] No single play marks a change from the traditional to the freer style. Shakespeare combined the two throughout his career, with Romeo and Juliet perhaps the best example of the mixing of the styles.[130] By the time of Romeo and Juliet, Richard II, and A Midsummer Night's Dream in the mid-1590s, Shakespeare had begun to write a more natural poetry. He increasingly tuned his metaphors and images to the needs of the drama itself.Pity by William Blake, 1795, Tate Britain, is an illustration of two similes in Macbeth: "And pity, like a naked new-born babe, / Striding the blast, or heaven's cherubim, hors'd / Upon the sightless couriers of the air".Shakespeare's standard poetic form was blank verse, composed in iambic pentameter. In practice, this meant that his verse was usually unrhymed and consisted of ten syllables to a line, spoken with a stress on every second syllable. The blank verse of his early plays is quite different from that of his later ones. It is often beautiful, but its sentences tend to start, pause, and finish at the end of lines, with the risk of monotony.[131] Once Shakespeare mastered traditional blank verse, he began to interrupt and vary its flow. This technique releases the new power and flexibility of the poetry in plays such as Julius Caesar and Hamlet. Shakespeare uses it, for example, to convey the turmoil in Hamlet's mind:[132]After Hamlet, Shakespeare varied his poetic style further, particularly in the more emotional passages of the late tragedies. The literary critic A. C. Bradley described this style as "more concentrated, rapid, varied, and, in construction, less regular, not seldom twisted or elliptical".[133] In the last phase of his career, Shakespeare adopted many techniques to achieve these effects. These included run-on lines, irregular pauses and stops, and extreme variations in sentence structure and length.[134] In Macbeth, for example, the language darts from one unrelated metaphor or simile to another: "was the hope drunk/ Wherein you dressed yourself?" (1.7.35–38); "...pity, like a naked new-born babe/ Striding the blast, or heaven's cherubim, hors'd/ Upon the sightless couriers of the air..." (1.7.21–25). The listener is challenged to complete the sense.[134] The late romances, with their shifts in time and surprising turns of plot, inspired a last poetic style in which long and short sentences are set against one another, clauses are piled up, subject and object are reversed, and words are omitted, creating an effect of spontaneity.[135]
Shakespeare's poetic genius was allied with a practical sense of the theatre.[136] Like all playwrights of the time, Shakespeare dramatised stories from sources such as Petrarch and Holinshed.[137] He reshaped each plot to create several centres of interest and show as many sides of a narrative to the audience as possible. This strength of design ensures that a Shakespeare play can survive translation, cutting and wide interpretation without loss to its core drama.[138] As Shakespeare’s mastery grew, he gave his characters clearer and more varied motivations and distinctive patterns of speech. He preserved aspects of his earlier style in the later plays, however. In his late romances, he deliberately returned to a more artificial style, which emphasised the illusion of theatre.[139]
Influence


Macbeth Consulting the Vision of the Armed Head. By Henry Fuseli, 1793–94. Folger Shakespeare Library, Washington.
Shakespeare's work has made a lasting impression on later theatre and literature. In particular, he expanded the dramatic potential of characterisation, plot, language, and genre.[140] Until Romeo and Juliet, for example, romance had not been viewed as a worthy topic for tragedy.[141] Soliloquies had been used mainly to convey information about characters or events; but Shakespeare used them to explore characters' minds.[142] His work heavily influenced later poetry. The Romantic poets attempted to revive Shakespearean verse drama, though with little success. Critic George Steiner described all English verse dramas from Coleridge to Tennyson as "feeble variations on Shakespearean themes."[143]
Shakespeare influenced novelists such as Thomas Hardy,[144] William Faulkner,[145] and Charles Dickens. Dickens often quoted Shakespeare, drawing 25 of his titles from Shakespeare's works.[146] The American novelist Herman Melville's soliloquies owe much to Shakespeare; his Captain Ahab in Moby-Dick is a classic tragic hero, inspired by King Lear.[147] Scholars have identified 20,000 pieces of music linked to Shakespeare's works. These include two operas by Giuseppe Verdi, Otello and Falstaff, whose critical standing compares with that of the source plays.[148] Shakespeare has also inspired many painters, including the Romantics and the Pre-Raphaelites.[149] The Swiss Romantic artist Henry Fuseli, a friend of William Blake, even translated Macbeth into German.[150] The psychoanalyst Sigmund Freud drew on Shakespearean psychology, in particular that of Hamlet, for his theories of human nature.[151]
In Shakespeare's day, English grammar and spelling were less standardised than they are now, and his use of language helped shape modern English.[152] Samuel Johnson quoted him more often than any other author in his A Dictionary of the English Language, the first serious work of its type.[153] Expressions such as "with bated breath" (Merchant of Venice) and "a foregone conclusion" (Othello) have found their way into everyday English speech.[154]
Critical reputation
Shakespeare was never revered in his lifetime, but he received his share of praise.[156] In 1598, the cleric and author Francis Meres singled him out from a group of English writers as "the most excellent" in both comedy and tragedy.[157] And the authors of the Parnassus plays at St John's College, Cambridge, numbered him with Chaucer, Gower and Spenser.[158] In the First Folio, Ben Jonson called Shakespeare the "Soul of the age, the applause, delight, the wonder of our stage", though he had remarked elsewhere that "Shakespeare wanted art".[159]


Ophelia (detail). By John Everett Millais, 1851–52. Tate Britain.
Between the Restoration of the monarchy in 1660 and the end of the seventeenth century, classical ideas were in vogue. As a result, critics of the time mostly rated Shakespeare below John Fletcher and Ben Jonson.[160] Thomas Rymer, for example, condemned Shakespeare for mixing the comic with the tragic. Nevertheless, poet and critic John Dryden rated Shakespeare highly, saying of Jonson, "I admire him, but I love Shakespeare".[161] For several decades, Rymer's view held sway; but during the eighteenth century, critics began to respond to Shakespeare on his own terms and acclaim what they termed his natural genius. A series of scholarly editions of his work, notably those of Samuel Johnson in 1765 and Edmond Malone in 1790, added to his growing reputation.[162] By 1800, he was firmly enshrined as the national poet.[163] In the eighteenth and nineteenth centuries, his reputation also spread abroad. Among those who championed him were the writers Voltaire, Goethe, Stendhal and Victor Hugo.[164]
During the Romantic era, Shakespeare was praised by the poet and literary philosopher Samuel Taylor Coleridge; and the critic August Wilhelm Schlegel translated his plays in the spirit of German Romanticism.[165] In the nineteenth century, critical admiration for Shakespeare's genius often bordered on adulation.[166] "That King Shakespeare," the essayist Thomas Carlyle wrote in 1840, "does not he shine, in crowned sovereignty, over us all, as the noblest, gentlest, yet strongest of rallying signs; indestructible".[167] The Victorians produced his plays as lavish spectacles on a grand scale.[168] The playwright and critic George Bernard Shaw mocked the cult of Shakespeare worship as "bardolatry". He claimed that the new naturalism of Ibsen's plays had made Shakespeare obsolete.[169]
The modernist revolution in the arts during the early twentieth century, far from discarding Shakespeare, eagerly enlisted his work in the service of the avant garde. The Expressionists in Germany and the Futurists in Moscow mounted productions of his plays. Marxist playwright and director Bertolt Brecht devised an epic theatre under the influence of Shakespeare. The poet and critic T. S. Eliot argued against Shaw that Shakespeare's "primitiveness" in fact made him truly modern.[170] Eliot, along with G. Wilson Knight and the school of New Criticism, led a movement towards a closer reading of Shakespeare's imagery. In the 1950s, a wave of new critical approaches replaced modernism and paved the way for "post-modern" studies of Shakespeare.[171] By the eighties, Shakespeare studies were open to movements such as structuralism, feminism, African American studies, and queer studies.[172]
Speculation about Shakespeare
Authorship
Around 150 years after Shakespeare's death, doubts began to emerge about the authorship of Shakespeare's works.[173] Alternative candidates proposed include Francis Bacon, Christopher Marlowe, and Edward de Vere, the Earl of Oxford.[174] Although all alternative candidates are almost universally rejected in academic circles, popular interest in the subject, particularly the Oxfordian theory, has continued into the 21st century.[175]
Religion
Some scholars claim that members of Shakespeare's family were Catholics, at a time when Catholic practice was against the law.[176] Shakespeare's mother, Mary Arden, certainly came from a pious Catholic family. The strongest evidence might be a Catholic statement of faith signed by John Shakespeare, found in 1757 in the rafters of his former house in Henley Street. The document is now lost, however, and scholars differ on its authenticity.[177] In 1591, the authorities reported that John had missed church "for fear of process for debt", a common Catholic excuse.[178] In 1606, William's daughter Susanna was listed among those who failed to attend Easter communion in Stratford.[178] Scholars find evidence both for and against Shakespeare's Catholicism in his plays, but the truth may be impossible to prove either way.[179]


Works
Comedies
Main article: Shakespearean comedy
All's Well That Ends Well‡
As You Like It
The Comedy of Errors
Love's Labour's Lost
Measure for Measure‡
The Merchant of Venice
The Merry Wives of Windsor
A Midsummer Night's Dream
Much Ado About Nothing
Pericles, Prince of Tyre*†[d]
The Taming of the Shrew
The Tempest*
Twelfth Night, or What You Will
The Two Gentlemen of Verona
The Two Noble Kinsmen*†[e]
The Winter's Tale*
Histories
Main article: Shakespearean history
King John
Richard II
Henry IV, part 1
Henry IV, part 2
Henry V
Henry VI, part 1† [f]
Henry VI, part 2
Henry VI, part 3
Richard III
Henry VIII†[g]
Tragedies
Main article: Shakespearean tragedy
Romeo and Juliet
Coriolanus
Titus Andronicus†[h]
Timon of Athens†[i]
Julius Caesar
Macbeth† [j]
Hamlet
Troilus and Cressida‡
King Lear
Othello
Antony and Cleopatra
Cymbeline*

Poems
Shakespeare's Sonnets
Venus and Adonis
The Rape of Lucrece
The Passionate Pilgrim[k]
The Phoenix and the Turtle
A Lover's Complaint
Lost plays
Love's Labour's Won
Cardenio†[l]
Apocrypha
Main article: Shakespeare Apocrypha
Arden of Faversham
The Birth of Merlin
Locrine
The London Prodigal
The Puritan
The Second Maiden's Tragedy
Sir John Oldcastle
Thomas Lord Cromwell
A Yorkshire Tragedy
Edward III
Sir Thomas More