The fourth argument is derived from the fact that one sense supports the testimony of another. "He that sees a fire may, if he doubt whether it be anything more than a bare fancy, feel it too." A bare fancy, Locke is sure, would not cause such acute pain. This comes back to the second and third arguments and may be criticized in the same way. If one could refer to a single observation of the fact that "real" things do not accompany ideas of the fancy and that they do accompany ideas of a different class, the argument would be unobjectionable. Wanting this observation, or something to take its place, nothing is proved. And as to the senses helping each other to "real" things, if each sense only gives the idea appropriate to it, it is not easy to see how two together prove more than one alone. In this section, too, Locke is assuming that "real" things belong to the world of things immediately perceived. He can, he says, make what characters he pleases on the paper before him, but once having made them, cannot choose but see them as they are. "Whence it is manifest, that they are not barely the sport and play of my own imagination, when I find that the characters that were made at the pleasure of my own thought, do not obey them; nor yet cease to be, whenever I shall fancy it; but continue to affect the senses constantly and regularly, according to the figures I made them." That is, the ideas which he concludes not to be ideas of imagination are the things "which continue to affect the senses," or the "real" things. There is little wonder that this author believed in "real" things. SEC. 32. Excellent work has been done by Berkeley in distinguishing samenesses. His treatment of sameness in sense third I have already quoted. His discussion of the infinite divisibility of finite lines,[57] a matter of which I shall speak more fully later, again brings out sense third. Almost his whole philosophy consists in the endeavor to keep clearly in mind the significance of sense seventh, and to develop what it implies. On the other hand, he has fallen into the error of confusing sense first and sense sixth, and of using this confusion to silence an objection to his doctrine. [57] "A Treatise Concerning the Principles of Human Knowledge," §§ 123-132. Ed. Fraser, Vol. I, pp. 220-225.