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    儒家之心学是全部儒学思想最基本的“硬核”，其他方面都是心学的延伸和展开。王阳明说“君子之学，惟求得其心”，心学就是强调主体自我的儒学，突出自信、自强、自律、自为，追求自我实现。“心学”的本质就是追求“内圣外王”价值取向，并为其寻求理论根据和修养方法的哲学。

    心学发端于春秋战国时期的孔子和孟子。孔子率先发现了人的自我，创立了以“仁学”“礼学”为核心的原始儒学，提出了“心安”的心性问题。孟子继承发展了孔子学说，比孔子更为突出地把心性之体表露出来，最先注意到心的作用。孟子认为：孔子所谓“仁”归根结底是人之心，“仁，人心也”（《孟子·告子上》）；“性”根源于“心”，“君子所性，仁义礼智根于心”（《孟子·告子上》）；只要尽心便能知性，“尽其心者，知其性也；知其性，则知天矣”（《孟子·告子上》）。由此，孟子确立了儒家心性之学的基本理念。儒家心性论的最初建构者是思孟学派，传承谱系是：由孔子到曾参，由曾参到子思，由子恩到孟子。其学术传承：孔子有《论语》，曾参有《大学》，子思有《中庸》，孟子有《孟子》。

    心学到了宋代，由北宋程颐开其端，南宋陆九渊大启其门径。清初的李二曲把陆九渊比作接续孟氏之后的第一人。“议论剀爽，令人当下心豁目明；简易直捷，孟氏之后仅见”。陆九渊不仅“发明”出“本心”，更重要的是他对此作了大致轮廓的描述：“心之体甚大。若能尽我之心，便与天同。”“此理塞宇宙”。宋代理学各学派都细致入微地谈论心性问题，有“无事袖手谈心性”之说，心性之学成为理学的代名词。

    明代中叶，心学集大成者王阳明首度提出“心学”二字，王阳明序《象山先生全集》日：“圣人之学，心学也。”阳明心学的经典表述，即著名的四句教：“无善无恶心之体，有善有恶意之动，知善知恶是良知，为善去恶是格物。”李二曲说：“至先生始拈‘致良知’三字，以泄千载不传之秘；一言之下，令人洞彻本面，愚夫愚妇，成可循之以入道，此万世功也。”良知是心之本体，没有私心物欲的心，是天理，是无善无恶的，也是我们追求的；当人们产生意念活动的时候，把这种意念加在事物上，这种意念就有了好恶，符合天理者善．不符合天理者恶；良知虽然无善无恶，但却自在地知善知恶，这是知的本体；一切学问、修养归结到一点，就是要为善去恶，即以良知为标准，按照自己的良知去行动。发动良知是为了发现良心。确立本体；发现良心，是为了发挥良能；发挥良能，是为了重建世界。至此心学开始有了清晰而独立的学术脉络。心学最不同于其他儒学的地方，在于其强调生命活泼的灵明体验。由此可见，严格意义上的“心学”产生于明代中叶，是儒学在新的社会条件下的新发展。心学一直延续到后世，对中华文化有着深远的影响。

（选自彭彦华《儒家心学与中国人的精神家园》，有删改）

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    To help the environment, many Americans have made the change from paper and plastic bags to reusable shopping bags.But a report by a Florida newspaper says that reusable shopping bags sold by some supermarkets have high levels of lead(铅), which can be dangerous to humans, especially young children.Now, there's a call for a rethink about the use of reusable shopping bags.

     “When our families go to the store looking for safe and healthy foods, the last thing they should be worrying about is a bag，”Charles Schumer, a government official said.“Quick and complete research will allow everyone to make right decisions.”

    The newspaper bought more than a dozen bags sold at Publix supermarkets from Florida supermarkets to test them for lead.The results showed that certain bags had lead levels that worried health officials.Some bags had enough lead in them to be considered dangerous waste if people were to throw the bags out with other rubbish.Lead in the bags is not likely to move onto food.But over time, paint (油漆) on the bags can break off and the bags can wear out.When this happens, lead can be freed.

    The affected (受影响的) bags were found in Florida.But Publix has more than 1，000 stores across America.Publix says that its bags don't break any laws about lead levels, but that they have asked the makers of the bags to reduce(降低) the lead levels in them.

    The bags with the highest levels of lead had beautiful designs and many pictures.Plain reusable bags without them are found to have little lead.People worried about lead levels in reusable bags can turn to cloth.Paper bags are also a good choice, since paper can be reused.

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