there are two styles of refutation: for some depend on the language used, while some are independent of language. those ways of producing the false appearance of an argument which depend on language are six in number: they are ambiguity, amphiboly, combination, division of words, accent, form of expression. of this we may assure ourselves both by induction, and by syllogistic proof based on this-and it may be on other assumptions as well-that this is the number of ways in which we might fall to mean the same thing by the same names or expressions. arguments such as the following depend upon ambiguity. ‘those learn who know: for it is those who know their letters who learn the letters dictated to them’. for to ‘learn’ is ambiguous; it signifies both ‘to understand’ by the use of knowledge, and also ‘to acquire knowledge’. again, ‘evils are good: for what needs to be is good, and evils must needs be’. for ‘what needs to be’ has a double meaning: it means what is inevitable, as often is the case with evils, too (for evil of some kind is inevitable), while on the other hand we say of good things as well that they ‘need to be’. moreover, ‘the same man is both seated and standing and he is both sick and in health: for it is he who stood up who is standing, and he who is recovering who is in health: but it is the seated man who stood up, and the sick man who was recovering’. for ‘the sick man does so and so’, or ‘has so and so done to him’ is not single in meaning: sometimes it means ‘the man who is sick or is seated now’, sometimes ‘the man who was sick formerly’. of course, the man who was recovering was the sick man, who really was sick at the time: but the man who is in health is not sick at the same time: he is ‘the sick man’ in the sense not that he is sick now, but that he was sick formerly. examples such as the following depend upon amphiboly: ‘i wish that you the enemy may capture’. also the thesis, ‘there must be knowledge of what one knows’: for it is possible by this phrase to mean that knowledge belongs to both the knower and the known. also, ‘there must be sight of what one sees: one sees the pillar: ergo the pillar has sight’. also, ‘what you profess to-be, that you profess to-be: you profess a stone to-be: ergo you profess-to-be a stone’. also, ‘speaking of the silent is possible’: for ‘speaking of the silent’ also has a double meaning: it may mean that the speaker is silent or that the things of which he speaks are so. there are three varieties of these ambiguities and amphibolies: (1) when either the expression or the name has strictly more than one meaning, e.g. aetos and the ‘dog’; (2) when by custom we use them so; (3) when words that have a simple sense taken alone have more than one meaning in combination; e.g. ‘knowing letters’. for each word, both ‘knowing’ and ‘letters’, possibly has a single meaning: but both together have more than one-either that the letters themselves have knowledge or that someone else has it of them.

amphiboly and ambiguity, then, depend on these modes of speech. upon the combination of words there depend instances such as the following: ‘a man can walk while sitting, and can write while not writing’. for the meaning is not the same if one divides the words and if one combines them in saying that ‘it is possible to walk-while-sitting’ and write while not writing]. the same applies to the latter phrase, too, if one combines the words ‘to write-while-not-writing’: for then it means that he has the power to write and not to write at once; whereas if one does not combine them, it means that when he is not writing he has the power to write. also, ‘he now if he has learnt his letters’. moreover, there is the saying that ‘one single thing if you can carry a crowd you can carry too’.

upon division depend the propositions that 5 is 2 and 3, and odd, and that the greater is equal: for it is that amount and more besides. for the same phrase would not be thought always to have the same meaning when divided and when combined, e.g. ‘i made thee a slave once a free man’, and ‘god-like achilles left fifty a hundred men’.

an argument depending upon accent it is not easy to construct in unwritten discussion; in written discussions and in poetry it is easier. thus (e.g.) some people emend homer against those who criticize as unnatural his expression to men ou kataputhetai ombro. for they solve the difficulty by a change of accent, pronouncing the ou with an acuter accent. also, in the passage about agamemnon’s dream, they say that zeus did not himself say ‘we grant him the fulfilment of his prayer’, but that he bade the dream grant it. instances such as these, then, turn upon the accentuation.

others come about owing to the form of expression used, when what is really different is expressed in the same form, e.g. a masculine thing by a feminine termination, or a feminine thing by a masculine, or a neuter by either a masculine or a feminine; or, again, when a quality is expressed by a termination proper to quantity or vice versa, or what is active by a passive word, or a state by an active word, and so forth with the other divisions previously’ laid down. for it is possible to use an expression to denote what does not belong to the class of actions at all as though it did so belong. thus (e.g.) ‘flourishing’ is a word which in the form of its expression is like ‘cutting’ or ‘building’: yet the one denotes a certain quality-i.e. a certain condition-while the other denotes a certain action. in the same manner also in the other instances.

refutations, then, that depend upon language are drawn from these common-place rules. of fallacies, on the other hand, that are independent of language there are seven kinds:

(1) that which depends upon accident:

(2) the use of an expression absolutely or not absolutely but with some qualification of respect or place, or time, or relation:

(3) that which depends upon ignorance of what ‘refutation’ is:

(4) that which depends upon the consequent:

(5) that which depends upon assuming the original conclusion:

(6) stating as cause what is not the cause:

(7) the making of more than one question into one.