SOCRATES: I find it interesting, Plato, that you say a living creature
PLATO: Yes, and with those I would agree. I should have said that living creatures
SOCRATES: Then you would agree that fleas and mice have souls, however insignificant.
PLATO: My definition does require that, yes.
SOCRATES: And do trees have souls, and blades of grass?
PLATO: You have used words to put me in this situation, Socrates. I will revise what I said — only animals have souls.
SOCRATES: But no, I have not only used words, for there is no distinction to be found between plants and animals, if you examine small enough creatures.
PLATO: You mean there are some creatures sharing the properties of plant and animal? Yes, I guess I can imagine such a thing, myself. Now I suppose you will force me into saying that only humans have souls. SOCRATES: No, on the contrary, I will ask you, what animals do you usually consider to have souls?
PLATO: Why, all higher animals — those which are able to think. SOCRATES: Then, at least higher animals are alive. Now can you truly consider a stalk of grass to be a living creature like yourself?
PLATO: Let me put it this way, Socrates: I can only imagine true life with a soul, and so I must discard grass as true life, though I could say it has the symptoms of life.
SOCRATES: I see. So you would classify soulless creatures as only
PLATO: Yes, that is right.
SOCRATES: And you have said that you consider the soul as the ability to think?
PLATO: Yes.
SOCRATES: Then you are really seeking the answer to “What is thinking?” PLATO: I have followed each step of your argument, Socrates, but this conclusion makes me uneasy.
SOCRATES: It has not been
PLATO: You are right, Socrates. And surely it is no simple task to explain thinking. It seems to me that the purest thought is the
SOCRATES: That is an interesting thought, Plato. Do you say that knowing is not so familiar as we think it is?
PLATO: Yes. Because we humans have knowledge, or convictions, we are humans, yet when we try to analyze knowing itself, it recedes, and evades us.
SOCRATES: Then had one not better be suspicious of what we call “knowing”, or “conviction”, and not take it so much for granted?
PLATO: Precisely. We must be cautious in saying “I know”, and we must ponder what it truly means to say “I know” when our minds would have us say it.
SOCRATES: True. If I asked you, “Are you alive?”, you would doubtless reply, “Yes, I am alive.” And if I asked you, “How do you know that you are alive?”, you would say “I
PLATO: Yes, I would certainly say something to that effect.
SOCRATES: Now let us suppose that a machine had been constructed which was capable of constructing English sentences and answering questions. And suppose I asked this English machine, “Are you alive?” and suppose it gave me precisely the same answers as you did. What would you say as to the validity of its answers?
PLATO: I would first of all object that no machine can know what words are, or mean. A machine merely deals with words in an abstract mechanical fashion, much as canning machines put fruit in cans.
SOCRATES: I do not accept your objections for two reasons. Surely you do not contend that the basic unit of human thought is the word? For it is well known that humans have nerve cells, the laws of whose operation are arithmetical. Secondly, you cautioned earlier that we must be wary of the verb “to know”, yet here you use it quite nonchalantly. What makes you say that no machine could ever “know” what words are, or mean?
PLATO: Socrates, do you argue that machines can know facts, as we humans do?
SOCRATES: You declared just now that you yourself cannot even explain what knowing is. How did you learn the verb “to know” as a child?
PLATO: Evidently, I assimilated it from hearing it used around me.
SOCRATES: Then it was by automatic action that you gained control of it.