(b) But, secondly, the imitator will commonly be least capable of understanding or imitating that part of a great writer which is most characteristic of him.  In every man’s writings there is something like himself and unlike others, which gives individuality.  To appreciate this latent quality would require a kindred mind, and minute study and observation.  There are a class of similarities which may be called undesigned coincidences, which are so remote as to be incapable of being borrowed from one another, and yet, when they are compared, find a natural explanation in their being the work of the same mind.  The imitator might copy the turns of style—­he might repeat images or illustrations, but he could not enter into the inner circle of Platonic philosophy.  He would understand that part of it which became popular in the next generation, as for example, the doctrine of ideas or of numbers:  he might approve of communism.  But the higher flights of Plato about the science of dialectic, or the unity of virtue, or a person who is above the law, would be unintelligible to him.

(c) The argument from imitation assumes a different character when the supposed imitations are associated with other passages having the impress of original genius.  The strength of the argument from undesigned coincidences of style is much increased when they are found side by side with thoughts and expressions which can only have come from a great original writer.  The great excellence, not only of the whole, but even of the parts of writings, is a strong proof of their genuineness—­for although the great writer may fall below, the forger or imitator cannot rise much above himself.  Whether we can attribute the worst parts of a work to a forger and the best to a great writer,—­as for example, in the case of some of Shakespeare’s plays,—­depends upon the probability that they have been interpolated, or have been the joint work of two writers; and this can only be established either by express evidence or by a comparison of other writings of the same class.  If the interpolation or double authorship of Greek writings in the time of Plato could be shown to be common, then a question, perhaps insoluble, would arise, not whether the whole, but whether parts of the Platonic dialogues are genuine, and, if parts only, which parts.  Hebrew prophecies and Homeric poems and Laws of Manu may have grown together in early times, but there is no reason to think that any of the dialogues of Plato is the result of a similar process of accumulation.  It is therefore rash to say with Oncken (Die Staatslehre des Aristoteles) that the form in which Aristotle knew the Laws of Plato must have been different from that in which they have come down to us.