The SOPHIST is one of Plato's more important dialogues. He probably wrote it when he had reached the age for retirement, -about 362 years before Christ.. Plato himself did not take part in his own dialogues, but introduced historical persons as characters. Usually Socrates was the star, but in this dialogue the Eleatic Stranger plays that role and talks with Theaetetus who is still a boy at the dramatic date of this conversation. Here Plato sets himself the task of developing a sound system of classification within which to characterize the professions and the possible philosophic positions. This effort led him to consider the central metaphysical and logical problems involved in the correct combination of concepts and in the little words 'is' and 'not'. In the process of resolving some of these problems Plato made major philosophic breakthroughs, and also, not quite coincidentally, laid the first firm foundations of grammar. While discussing the combination of concepts the Eleatic Stranger used the alphabet as an example, explaining to Theaetetus that some letters of the alphabet fit together naturally to form larger units called syllables, while other letters do not. Later on in the discussion a new, but related topic was introduced by the Stranger: -- "Well, come on then, we will talk about words and their groupings in the same way that we did about letters and syllables. For what we are now seeking seems likely to be somewhere in this area of thought. -- What sort of a question will you expect me to answer about words? -- Whether they all join together with each other or none does, or whether some fit together into larger unities, but others do not. -- Well, it is clear to me at least that some do, but others do not. -- Maybe then you mean something like this: If words signify something when they are spoken one after another in succession, then they fit together; whichever words do not make any sense when they are spoken in succession do not then fit together in a whole. -- How do you mean what you said? -- I meant just what I thought that you intended when you gave me your approval: in a certain sense we have two kinds of expressions that make clear in speech what we mean about reality. -- What do you mean? -- One kind of expression we call a name (or a noun); the other we call an action-word (or a verb). -- Describe each for me. -- We generally call the one that refers clearly to actions an action-word. -- Oh, yes. -- And the spoken sign that refers to whatever performs those actions we generally call a name. -- Completely so. -- Well then a statement (or a sentence) is never just a string of names, nor just of action-words spoken in succession without any names. -- I do not get this. -- Then you probably agreed with me just now only because you were looking at some other aspect, whereas I wanted just to make this statement by itself: that a statement is not the speaking of these words in this way (just names or just action-words) in sequence. -- How then in particular? -- For instance, the string of words 'walks runs sleeps' does not make a statement, nor will it be more likely to happen, even if you say in serial succession whatever words there are that refer to acts and activities. -- Aha, and what about names? -- Likewise, neither does the string of words 'lion stag horse' constitute a statement in any way or degree despite its serial succession, nor will it whenever all the names are spoken that have been given to whoever performs such acts. For the sounds uttered do not clearly state any activity or inactivity of any existing or non-existing thing, until the speaker joins the action-words with the names. Then at that point they united and this first connection straightway became a statement, the first and almost the simplest and shortest of statements. -- How then do you make such a statement? Whenever anyone says that 'a man understands', do you agree that this is the simplest and most minimal kind of statement? -- I do. -- It does indeed in mysterious wise itself clearly inform us about eternal things or occurring events or reported happenings or future possibilities, and it does not just assign names, but it accomplishes something by interweaving action-words with names. Accordingly, we claim that our word-combination asserts something and does not just assign names; specifically, it is to this word-combination that we assign the name of statement and call a sentence. -- And correctly so, indeed."