為什么演講稿范文3篇

　　簡介：在美國，80%的女孩在她們10歲的時(shí)候便開始節(jié)食。神經(jīng)學(xué)家sandra aamodt結(jié)合自己的親身經(jīng)歷，講述大腦是如何控制我們的身體的。節(jié)食減肥為何沒效果?來聽聽她的說法吧!

　　three and a half years ago, i made one of the best decisions of my life. as my new year's resolution, i gave up dieting, stopped worrying about my weight, and learned to eat mindfully. now i eat whenever i'm hungry, and i've lost 10 pounds.

　　this was me at age 13, when i started my first diet. i look at that picture now, and i think, you did not need a diet, you needed a fashion consult. (laughter) but i thought i needed to lose weight, and when i gained it back, of course i blamed myself. and for the next three decades, i was on and off various diets. no matter what i tried, the weight i'd lost always came back. i'm sure many of you know the feeling.

　　as a neuroscientist, i wondered, why is this so hard? obviously, how much you weigh depends on how much you eat and how much energy you burn. what most people don't realize is that hunger and energy use are controlled by the brain, mostly without your awareness. your brain does a lot of its work behind the scenes, and that is a good thing, because your conscious mind -- how do we put this politely? -- it's easily distracted. it's good that you don't have to remember to breathe when you get caught up in a movie. you don't forget how to walk because you're thinking about what to have for dinner.

　　your brain also has its own sense of what you should weigh, no matter what you consciously believe. this is called your set point, but that's a misleading term, because it's actually a range of about 10 or 15 pounds. you can use lifestyle choices to move your weight up and down within that range, but it's much, much harder to stay outside of it. the hypothalamus, the part of the brain that regulates body weight, there are more than a dozen chemical signals in the brain that tell your body to gain weight, more than another dozen that tell your body to lose it, and the system works like a thermostat, responding to signals from the body by adjusting hunger, activity and metabolism, to keep your weight stable as conditions change. that's what a thermostat does, right? it keeps the temperature in your house the same as the weather changes outside. now you can try to change the temperature in your house by opening a window in the winter, but that's not going to change the setting on the thermostat, which will respond by kicking on the furnace to warm the place back up.

　　your brain works exactly the same way, responding to weight loss by using powerful tools to push your body back to what it considers normal. if you lose a lot of weight, your brain reacts as if you were starving, and whether you started out fat or thin, your brain's response is exactly the same. we would love to think that your brain could tell whether you need to lose weight or not, but it can't. if you do lose a lot of weight, you become hungry, and your muscles burn less energy. dr. rudy leibel of columbia university has found that people who have lost 10 percent of their body weight burn 250 to 400 calories less because their metabolism is suppressed. that's a lot of food. this means that a successful dieter must eat this much less forever than someone of the same weight who has always been thin.

　　from an evolutionary perspective, your body's resistance to weight loss makes sense. when food was scarce, our ancestors' survival depended on conserving energy, and regaining the weight when food was available would have protected them against the next shortage. over the course of human history, starvation has been a much bigger problem than overeating. this may explain a very sad fact: set points can go up, but they rarely go down. now, if your mother ever mentioned that life is not fair, this is the kind of thing she was talking about. (laughter) successful dieting doesn't lower your set point. even after you've kept the weight off for as long as seven years, your brain keeps trying to make you gain it back. if that weight loss had been due to a long famine, that would be a sensible response. in our modern world of drive-thru burgers, it's not working out so well for many of us. that difference between our ancestral past and our abundant present is the reason that dr. yoni freedhoff of the university of ottawa would like to take some of his patients back to a time when food was less available, and it's also the reason that changing the food environment is really going to be the most effective solution to obesity.

　　sadly, a temporary weight gain can become permanent. if you stay at a high weight for too long, probably a matter of years for most of us, your brain may decide that that's the new normal.

　　psychologists classify eaters into two groups, those who rely on their hunger and those who try to control their eating through willpower, like most dieters. let's call them intuitive eaters and controlled eaters. the interesting thing is that intuitive eaters are less likely to be overweight, and they spend less time thinking about food. controlled eaters are more vulnerable to overeating in response to advertising, super-sizing, and the all-you-can-eat buffet. and a small indulgence, like eating one scoop of ice cream, is more likely to lead to a food binge in controlled eaters. children are especially vulnerable to this cycle of dieting and then binging.

　　several long-term studies have shown that girls who diet in their early teenage years are three times more likely to become overweight five years later, even if they started at a normal weight, and all of these studies found that the same factors that predicted weight gain also predicted the development of eating disorders. the other factor, by the way, those of you who are parents, was being teased by family members about their weight. so don't do that. (laughter)

　　i left almost all my graphs at home, but i couldn't resist throwing in just this one, because i'm a geek, and that's how i roll. (laughter) this is a study that looked at the risk of death over a 14-year period based on four healthy habits: eating enough fruits and vegetables, exercise three times a week, not smoking, and drinking in moderation. let's start by looking at the normal weight people in the study. the height of the bars is the risk of death, and those zero, one, two, three, four numbers on the horizontal axis are the number of those healthy habits that a given person had. and as you'd expect, the healthier the lifestyle, the less likely people were to die during the study. now let's look at what happens in overweight people.

　　the ones that had no healthy habits had a higher risk of death. adding just one healthy habit pulls overweight people back into the normal range. for obese people with no healthy habits, the risk is very high, seven times higher than the healthiest groups in the study. but a healthy lifestyle helps obese people too. in fact, if you look only at the group with all four healthy habits, you can see that weight makes very little difference. you can take control of your health by taking control of your lifestyle, even if you can't lose weight and keep it off.

　　diets don't have very much reliability. five years after a diet, most people have regained the weight. forty percent of them have gained even more. if you think about this, the typical outcome of dieting is that you're more likely to gain weight in the long run than to lose it.

　　if i've convinced you that dieting might be a problem, the next question is, what do you do about it? and my answer, in a word, is mindfulness. i'm not saying you need to learn to meditate or take up yoga. i'm talking about mindful eating: learning to understand your body's signals so that you eat when you're hungry and stop when you're full, because a lot of weight gain boils down to eating when you're not hungry. how do you do it? give yourself permission to eat as much as you want, and then work on figuring out what makes your body feel good. sit down to regular meals without distractions. think about how your body feels when you start to eat and when you stop, and let your hunger decide when you should be done. it took about a year for me to learn this, but it's really been worth it. i am so much more relaxed around food than i have ever been in my life. i often don't think about it. i forget we have chocolate in the house. it's like aliens have taken over my brain. it's just completely different. i should say that this approach to eating probably won't make you lose weight unless you often eat when you're not hungry, but doctors don't know of any approach that makes significant weight loss in a lot of people, and that is why a lot of people are now focusing on preventing weight gain instead of promoting weight loss. let's face it: if diets worked, we'd all be thin already. (laughter)

　　why do we keep doing the same thing and expecting different results? diets may seem harmless, but they actually do a lot of collateral damage. at worst, they ruin lives: weight obsession leads to eating disorders, especially in young kids. in the u.s., we have 80 percent of 10-year-old girls say they've been on a diet. our daughters have learned to measure their worth by the wrong scale. even at its best, dieting is a waste of time and energy. it takes willpower which you could be using to help your kids with their homework or to finish that important work project, and because willpower is limited, any strategy that relies on its consistent application is pretty much guaranteed to eventually fail you when your attention moves on to something else.

　　let me leave you with one last thought. what if we told all those dieting girls that it's okay to eat when they're hungry? what if we taught them to work with their appetite instead of fearing it? i think most of them would be happier and healthier, and as adults, many of them would probably be thinner. i wish someone had told me that back when i was 13.

　　thanks.

　　(applause)

　　i have the answer to a question that we've all asked. the question is, why is it that the letter x represents the unknown? now i know we learned that in math class, but now it's everywhere in the culture -- the x prize, the x-files, project x, tedx. where'd that come from?

　　about six years ago i decided that i would learn arabic, which turns out to be a supremely logical language. to write a word or a phrase or a sentence in arabic is like crafting an equation, because every part is extremely precise and carries a lot of information. that's one of the reasons so much of what we've come to think of as western science and mathematics and engineering was really worked out in the first few centuries of the common era by the persians and the arabs and the turks.

　　this includes the little system in arabic called al-jebra. and al-jebr roughly translates to "the system for reconciling disparate parts." al-jebr finally came into english as algebra. one example among many.

　　the arabic texts containing this mathematical wisdom finally made their way to europe -- which is to say spain -- in the 11th and 12th centuries. and when they arrived there was tremendous interest in translating this wisdom into a european language.

　　but there were problems. one problem is there are some sounds in arabic that just don't make it through a european voice box without lots of practice. trust me on that one. also, those very sounds tend not to be represented by the characters that are available in european languages.

　　here's one of the culprits. this is the letter sheen, and it makes the sound we think of as sh -- "sh." it's also the very first letter of the word shalan, which means "something" just like the the english word "something" -- some undefined, unknown thing.

　　now in arabic, we can make this definite by adding the definite article "al." so this is al-shalan -- the unknown thing. and this is a word that appears throughout early mathematics, such as this 10th century derivation of proofs.

　　the problem for the medieval spanish scholars who were tasked with translating this material is that the letter sheen and the word shalan can't be rendered into spanish because spanish doesn't have that sh, that "sh" sound. so by convention, they created a rule in which they borrowed the ck sound, "ck" sound, from the classical greek in the form of the letter kai.

　　later when this material was translated into a common european language, which is to say latin, they simply replaced the greek kai with the latin x. and once that happened, once this material was in latin, it formed the basis for mathematics textbooks for almost 600 years.

　　but now we have the answer to our question. why is it that x is the unknown? x is the unknown because you can't say "sh" in spanish. (laughter) and i thought that was worth sharing.

　　(applause)

　　尊敬的各位老師，同學(xué)們，大家好！

　　我是法學(xué)院大四學(xué)生李明，我演講的題目是《我為什么要學(xué)法律》

　　很多人聽到這個(gè)題目，一定以為我太把這次演講比賽當(dāng)做兒戲了。一個(gè)簡單的專業(yè)選擇的問題，與我們今天的主題“中國夢”能有多大的關(guān)聯(lián)呢？其實(shí)在初入燕園之時(shí)，我也只曾在大眾媒體和長輩的口耳相傳中聽得法律職業(yè)者的種種評價(jià)，也只曾知道“憲法是我國根本大法”之類的政治課本知識，也只曾在路過國徽高懸的莊嚴(yán)肅穆的法院門口時(shí)好奇的回望。而今，我即將從北大法學(xué)院畢業(yè)，成為一名光榮的北大法律人，我所應(yīng)當(dāng)肩負(fù)的責(zé)任是什么，我可能實(shí)現(xiàn)的人生價(jià)值在歷史的坐標(biāo)下又是什么？

　　我想，這個(gè)簡單的問題，不僅僅是我四年燕園求學(xué)中努力求索的精神真諦，而且將是指導(dǎo)我未來發(fā)展的永恒旗幟。法律人，應(yīng)該有著怎樣的中國夢，這需要我們用整個(gè)人生去回答。

　　法律人的中國夢，是維護(hù)公民合法利益的權(quán)利之夢。法治，絕不應(yīng)當(dāng)僅僅是宏大的制度構(gòu)建，而也應(yīng)當(dāng)構(gòu)筑起公民權(quán)利的堡壘，讓苦干多年農(nóng)民工兄弟早日拿到血汗錢，讓征地拆遷中的血案不再上演，讓猖獗一時(shí)的刑訊逼供無處藏身。法學(xué)家耶林告訴我們，要“為權(quán)利而斗爭”，因?yàn)楫?dāng)每個(gè)人都在強(qiáng)權(quán)面前退卻的時(shí)候，整個(gè)共同體的利益將不得不被放棄。法律人站在公民權(quán)利與強(qiáng)權(quán)暴力交鋒的戰(zhàn)場，捍衛(wèi)每個(gè)人的權(quán)利，捍衛(wèi)每個(gè)人的中國夢。

　　法律人的中國夢，是追求社會(huì)公平的正義之夢。堅(jiān)韌的法律人，讓蒼南縣政府做到了被告席上，與浙江普通農(nóng)民包鄭照對簿公堂。執(zhí)著的法律人，讓佘祥林、趙作海獲得了他們應(yīng)得的國家賠償，使冤案昭雪，真相大白。讓比太陽還要光輝的公平正義灑滿人間，是法律人永恒的信條。

　　法律人的中國夢，是讓中華民族真正實(shí)現(xiàn)民主與文明的復(fù)興之夢。法律人夢想著讓每個(gè)人都有行使民主權(quán)利的機(jī)會(huì)，共享國家發(fā)展帶來的成果；法律人希望能夠用制度構(gòu)建約束權(quán)力的牢籠，讓腐木與蛀蟲無處藏身；法律人希望能夠走出一條具有中國特色的民主、法治之路，讓中華民族以更加文明的姿態(tài)屹立于世界東方，讓中國夢成為世界所景仰的精神價(jià)值。

　　也許還有人僅僅是為了在訴訟和爭議中獲得利益，利用法律規(guī)避責(zé)任而無視事實(shí)真相的存在；也許還有人僅僅是為了粉飾太平，偏袒強(qiáng)者欺壓弱者，息事寧人而將公平正義束之高閣；也許還有人僅僅是為了維護(hù)舊秩序的穩(wěn)定，坐擁惡法，助紂為虐。但中國夢的號角已經(jīng)吹響，駛向中華民族偉大復(fù)興的巨輪已經(jīng)起航，一切的不完美，都等待著我們?nèi)ジ淖�。我們怎樣，中國便怎樣。我們是什么，中國便是什么。我們有光明，中國便不再黑暗�?/p>

　　在古希臘神話中，代表正義的女神是這樣的形象：她雙眼緊蒙，代表不受干擾和高貴的邏輯理性；她手握天平，代表絕對公平絕不偏袒；她手握利劍，代表踐行正義絕不姑息。法律人，正是懷著崇高的理性精神，踐行對社會(huì)公平正義的追求，在推進(jìn)人類文明的道路上披荊斬棘，為公民權(quán)利而戰(zhàn)，為公平正義而戰(zhàn)，為社會(huì)進(jìn)步和民族復(fù)興而戰(zhàn)！

　　我為什么要學(xué)法律，我想，法律人的中國夢，已經(jīng)告訴我答案。

　　我叫馬巖松，我是個(gè)建筑師，我今天講的是，我們?yōu)槭裁匆�談未來，我曾�?jīng)被一個(gè)很重要的批評家問過一個(gè)問題，他說，未來將會(huì)是什么，當(dāng)時(shí)我就想怎么回答這個(gè)問題。最后我給他一個(gè)答案呢，就是未來就是過去。

　　大概是XX年吧，這時(shí)候我已經(jīng)在北京工作，我們做了一個(gè)競賽，這個(gè)競賽在中國的一個(gè)大城市，競賽要求建一個(gè)四百米的一個(gè)樓，然后政府的人說，雖然我們寫的是400米，但是呢，你們可以來表達(dá)你們認(rèn)為的一個(gè)高度，他這個(gè)話呢大家都明白了，就是他想要一個(gè)更高的，他要一個(gè)更高的樓，來表達(dá)這個(gè)城市的一個(gè)信心。結(jié)果呢，所有的建筑師都設(shè)計(jì)了一個(gè)高于400米的，高于400米，500米，600米，當(dāng)時(shí)還沒有迪拜這個(gè)800米的事兒，然后我當(dāng)時(shí)就想，那我就來一個(gè)800米的吧。然后我跟政府匯報(bào)的第一句就是你想要一個(gè)世界第一高的樓嗎?我們這是一個(gè)800米的，但是這個(gè)800米的樓呢，其實(shí)只有400米，但是它是兩截，400米上去了然后又轉(zhuǎn)下來，一共800米。等于是樓頂又回到了地面，然后我們就輸了，不但輸了，而且十幾年過去了，我們現(xiàn)在還沒拿到設(shè)計(jì)費(fèi)，就是他們生氣了。生氣呢，我覺得可能是這個(gè)，對這個(gè)玩笑有點(diǎn)接受不了，很多地方都想建超越盤，建一個(gè)更高的樓，用更高的樓代表他們的野心�？墒乾F(xiàn)在時(shí)間又不一樣了，現(xiàn)在我們已經(jīng)開始上火星了，技術(shù)已經(jīng)很發(fā)達(dá)，建一個(gè)高層建筑其實(shí)并不難，挑戰(zhàn)不了技術(shù)，只是挑戰(zhàn)錢，所以高層建筑就慢慢變成了權(quán)力和資本的一個(gè)紀(jì)念碑，所以這個(gè)時(shí)代呢，我覺得已經(jīng)不是再去贊美權(quán)力和資本的時(shí)代了。都想建大樓，都想用高樓來代表他們的信心，來代表一個(gè)城市創(chuàng)造力的時(shí)候，我就覺得非常愚蠢，所以把這個(gè)玩笑當(dāng)成是一種對現(xiàn)實(shí)的批判。每一個(gè)對現(xiàn)實(shí)的批判，我都認(rèn)為指向一個(gè)更好的未來。但這個(gè)未來呢，就永遠(yuǎn)不發(fā)生。

　　每一次我們的提案都是輸，直到我們做了一個(gè)競賽，是在國外，我們贏了一個(gè)高層建筑的競賽，這個(gè)項(xiàng)目在加拿大，在北美，大家都直到我們今天中國的城市都是在山寨北美，北美是高層建筑，是這種現(xiàn)代城市的故鄉(xiāng)，我們在北美能設(shè)計(jì)一個(gè)房子，我就想能不能去，不去跟其他的樓一樣，去搶這樣的高度，力量，我設(shè)計(jì)一個(gè)自然的高層建筑，因?yàn)楹芏嗳苏f這個(gè)曲線像一個(gè)女人的曲線，然后加拿大管這個(gè)樓叫“夢露大廈”，然后我們就有一天收到一封信，就說你們?nèi)雵�了，這時(shí)候我覺得非常地習(xí)慣，因?yàn)槿雵�之前，我們�?jīng)常入圍，但是我們確定他們不會(huì)選我們。第一因?yàn)槲覀兪侵袊�的，中國的建筑師，在北美設(shè)計(jì)一個(gè)房子，以前從來沒聽說過。第二，我覺得他們讓我們?nèi)雵�，可能是看上我們的這個(gè)圖，跟他們以前建造的這些高樓，都不一樣。但是當(dāng)建造的時(shí)候，可能所有人都該說，怎么建呀?結(jié)構(gòu)是什么樣?會(huì)不會(huì)花很多錢?但我還是去了，我一點(diǎn)也不緊張。我覺得，我覺得我就是抱著一種不會(huì)被選上這么一個(gè)心態(tài)去。不會(huì)被選上的心態(tài)對我來說是非常重要的。如果被選上了，我會(huì)覺得心里不舒服，我會(huì)覺得他們看懂我了，我會(huì)覺得我可能諂媚他們了，為什么我的批判，我的玩笑，我對他們的刺激，還能被他們高興地接受。所以那樣的結(jié)果，可能對我來說更殘酷的，我基本上已經(jīng)習(xí)慣了不被接受的，不能建的這個(gè)狀態(tài)。又過了兩個(gè)月，他們最后決定要建我們這個(gè)樓了，我覺得他們瘋了，但我又說不出來為什么他們瘋了，我只知道大部分人不會(huì)做這樣的決定，我也為他們捏把汗，因?yàn)槟菚r(shí)候我還基本上沒怎么工作過，我也沒建過什么房子。我想如果你們誰家想蓋一房子，找一建筑師，至少這個(gè)人以前是蓋過房子的吧，更何況是建一個(gè)城市地標(biāo)。所以這件事突然讓我有了信心，我覺得我好像也能建房子了。

　　但我又有一點(diǎn)害怕，我覺得我批判，一個(gè)指向未來的建筑，怎么說蓋就蓋起來了，這個(gè)未來是不是，本來就不是未來啊。所以當(dāng)這個(gè)高層建筑在北美開工的時(shí)候，我就在想，我真正的未來是什么?山水城市，我認(rèn)為是源于對未來的渴望，是要解決現(xiàn)實(shí)的問題，是想建造一個(gè)有情感的、有自然的、有生活的這樣的城市。我們現(xiàn)在呢，又是在這么一個(gè)階段，就是生活在自己的臆想里面，你要問我具體的問題，說這個(gè)到底是什么，我也不知道。但是我喜歡這種狀態(tài)，讓我越來越接近未來，我希望能跟未來有一個(gè)對話，謝謝!