Next, the machine would be able to read, or using his word, to 'scan' the square of tape on which it rested.
然后，这个机器还要可以读出，或者用他的话，"扫描"它所在的格子。
It would still of course be able to write symbols, but now also to erase them.
它不但可以写入符号，现在还可以清除符号。
But it would only be able to move one place to the left or the right at a time.
但它一次只能移动一个格子，无论向左或向右。
What role remained to the human operator of the typewriter?
现在，打印机的操作者要扮演什么角色呢？
He did mention the possibility of what he called 'choice machines', in which an external operator would have the job of making decisions at certain points.
他提到了“决策机器”，外在的操作者，负责在特定时刻做出决策。
But the thrust of his argument was directed at what he called automatic machines, in which human intervention would play no part.
但问题是，他的想法的关键在于他所说的“自动”机器，它应该不需要人类的干预。
For the goal of his development was the discussion of what Hardy had called 'a miraculous machine'—
因为他的目标是哈代所说的"超自然的机器"——
a mechanical process which could work on Hilbert's decision problem, reading a mathematical assertion presented to it, and eventually writing a verdict as to whether it was provable or not.
希尔伯特问题中的那个机械程序，能够判断任意数学命题是否可以证明，
The whole point was that it should do so without the interference of human judgment, imagination or intelligence.
最重要的是，它不需要人类智力的干预。
Any 'automatic machine' would work away by itself, reading and writing, moving to and fro, all in accordance with the way in which it was constructed.
“自动机器”可以自己工作，根据它的构造，自动地读出和写入，或来回移动。
At every step its behaviour would be completely determined by the configuration it was in and the symbol it had read.
它每一步的行为，完全由它的状态和读出的符号来决定。
To be precise, the construction of the machine would determine, for each combination of configuration and symbol scanned:
准确地说，对于每一种状态和读出符号的组合，机器的构造决定了：
whether to write a new (specified) symbol in a blank square, to leave the existing one unchanged, or to erase it and leave a blank square
写入一个新的（确定的）符号，还是保持现有符号不变，还是清除它并留下空格；
whether to remain in the same configuration, or to change to some other (specified) configuration
保持当前的状态，还是变成另一个（确定的）状态；
whether to move to the square on the left, or to the right, or to stay in the same position.
向左移动一格，或向右移动一格，还是留在当前位置。
If all this information, defining an automatic machine, were written out, it would form a 'table of behaviour' of a finite size.
如果把所有这些定义自动机器的信息写出来，就会形成一个有限大小的“行为表”。
It would completely define the machine in the sense that whether physically constructed or not, the table would hold all the relevant information about it.
无论在物理上如何制造这台机器，这张表都将完全定义机器的行为，
From this abstract point of view, the table was the machine.
如果用抽象的观点来看，这个表就是那机器。
Every different possible table would define a machine with a different kind of behaviour.
不同的表，可以定义不同行为的机器。
There would be infinitely many possible tables, corresponding to infinitely many possible machines.
可以想见，这样的表格会有无数种，也就是有无数种不同行为的机器。