In 1905, as part of his special theory of relativity, Albert Einstein published the point that a large amount of energy could be released from a small amount of matter. This was expressed by equation E=mc2 (energy equals mass times the speed of light squared). But bombs were not what Einstein had in mind when he published this equation.

In 1929, he publicly declared that if a war broke out he would “refuse to do war service, direct or indirect…” His position would change in 1933, as the result of Adolf Hitler’s coming into power in Germany.

Einstein’s greatest role in the invention of the atom bomb was signing a letter to President Franklin Roosevelt urging that the bomb be built because some physicists feared that Germany might be working on an atom bomb. Among those concerned were physicists Leo Szilard and Eugene Wigner. But Szilard and Wigner had no influence on those in power. So in July 1939 they explained the problem to someone who did: Albert Einstein. After talking with Einstein, in August 1939 Szilard wrote a letter to President Roosevelt with Einstein’s signature on it, which was delivered to Roosevelt in October 1939.

Germany had invaded Poland the previous month; the time was ripe for action. That October the research of A-bomb began but proceeded slowly because the invention of the atom bomb seemed distant and unlikely. In April 1940 an Einstein letter, ghostwritten by Szilard, pressed the researchers on the need for “greater speed”.

As the realization of nuclear weapons grew near, Einstein looked beyond the current war to future problems that such weapons could bring. He wrote to his friend about his fear about the future use of the A-bomb.

The atom bombings of Japan occurred three months after Germany gave in.

In November 1954, five months before his death, Einstein summarized his feelings about his role in the creation of the atom bomb: “I made one great mistake in my life…when I signed a letter to President Roosevelt recommending that atom bombs be made; but there was some justification—the danger that the Germans would make them.”

History is a record of what has happened in the past.【小题1】The really fascinating thing is that much of history has been repeated time and again. It allows us to learn from the past, both the mistakes made and the successes achieved.

One of the benefits of history is reading how other people both famous and totally unknown have overcome tremendous challenges in their life. These challenges, although particular to a person, or to a certain time in the past, or occurring in a different country or culture, all convey the same thing.【小题2】

【小题3】He encountered many failures while on the road to finally inventing the modern day light bulb. He could be held out as an example of a person who never gave up.【小题4】However, he did not let those failures stop him. He had a dream and he just kept trying different things until he did reach success.

Or, consider the story of Abraham Lincoln who managed to become President of the United States even though he suffered many setbacks and personal losses. Most of us only realize the success of Mr. Lincoln becoming President.【小题5】His life was not an easy one. His story is one that motivates us to keep moving forward no matter what obstacles we have in life.

【小题1】People use money to buy food, furniture, books, bicycles and hundreds of other things they need or want. When they work, they usually get paid in money.

Most of the money today is made of metal or paper.【小题2】One of the first kinds of money was shells.

Shells were not the only things used as money. In China, cloth and knives were used. In the Philippine Islands, rice was used as money for a long time. Elephant tusks, monkey tails and salt were used as money in parts of Africa.

The first metal coins were made in China. They were round and had a square hole in the centre.【小题3】

Different countries have used different metals and designs for their money.【小题4】Sweden and Russia used copper (铜) to make their money. Later some countries began to make coins of gold and silver.

But even gold and silver were inconvenient if you had to buy something expensive. Again the Chinese thought of a way to improve money.【小题5】The first paper money looked more like a note from one person to another than the paper money used today.

Money has had an interesting history from the days of shell money until today.