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Von Neumann had also seen that it was possible to interfere with the stored instructions, but had done so in only one very particular way.
冯·诺伊曼也看到了改变指令的可能性，但他是通过一种非常古怪的方法实现的。
If a stored instruction had the effect of 'taking the number at address 786', then he had noticed that it would be convenient to be able to add 1 into the 786, so that it gave the effect of 'taking the number at address 787'.
他的想法是，如果一条指令是"读取地址786中的数"，那么可以很方便地把786加上1，这样它就会变成"读取地址787中的数"。
This was just what was needed for working along a long list of numbers, stored in locations 786, 787, 788, 789 and so forth, as would so frequently occur in large calculations.
这在处理存储在786, 787, 788, 789等位置的连续指令时，是非常好用的，而这种情况恰恰在大型计算中非常常见。
He had programmed the idea of going to the 'next' address, so that it did not have to be spelt out in explicit form.
他的想法是，机器可以随时跳到下一个地址，这样可以简化程序。
But von Neumann went no further than this.
但是，冯·诺伊曼只止步于此，
In fact, he actually proposed a way of ensuring that instructions could not be modified in any other way than this.
他甚至还提出一个方案，以确保这是改变指令的唯一方式，其他方式都被禁止。
The Turing approach was very different.
而图灵的想法，则完全不同。
Commenting on this feature of modifying instructions, he wrote in the report: 'This gives the machine the possiblity of constructing its own orders. ...This can be very powerful.'
他在报告中提出了可变指令的特性："这使机器可以自动地构造指令……这是非常有用的。"
In 1945 both he and the ENIAC team had hit upon the idea of storing the instructions inside the machine.
1945年，他和ENIAC小组都忽然意识到，指令可以存储在机器内部。
But this in itself said nothing about the next step, that of exploiting the fact that the instructions could now themselves be changed in the course of running the machine.
但这个想法本身，并没有引出更深入的问题，也就是要利用这样一个事实：机器在运行时，指令可以发生改变。
This was what he now went on to explain.
这也正是图灵接下来要面对的问题。
