Of this the following may be taken as a simple example. "The sun rises; clouds form; clouds cover the sky; lightning flashes; thunder roars." It is easy in these expressions to observe, what were the sensations, and in what order they succeeded one another. It is also observable, that the order is denoted by so many Predications; and that Predication is our only expedient for denoting their order. First sensation, "sight of the sun;" second sensation, "rising of the sun;" these two denoted shortly and in their order by the Predication, "the sun rises." Third sensation, "sight of clouds;" fourth sensation, "forming of clouds;" these two again shortly denoted in their order by the Predication, "clouds form." The next, "clouds cover the sky," needs no further explanation; but there is a peculiar artifice of language in the two following Predications; "lightning flashes," "thunder roars," which deserves to be well understood. "Lightning flashes;" here there is but one sensation, the sensation of sight, which we call a flash. But there are various kinds of flashes; this is a peculiar one, and I want to mark peculiarly what it is. It is not a flash on the earth, but a flash in the sky; it will not, however, sufficiently distinguish the flash in question, to say, the sky flashes, because other flashes come from the sky. What then is my contrivance? I form the fancy of a cause of this particular flash, though I know nothing concerning it, and for this unknown cause I invent a name, and call it lightning. I have then an expression which always accurately {186} marks the sensation I mean to denote: I say, "the lightning flashes," "a flash of lightning," and so on. "Thunder roars," is another case of the same artifice. The noise here is the only sensation; but in order to distinguish it from all other noises, I invent a name for its unknown cause, and by its means can mark the sensation with perfect precision. The Fictions, after this manner resorted to, for the purpose of marking; though important among the artifices of naming; have contributed largely to the misdirection of thought. By the unfortunate ambiguity of the _Copula_, EXISTENCE is affirmed of them in every Predication into which they enter. The idea of EXISTENCE becomes, by this means, inseparable from them; and their true nature, as Creatures of the mind, and nothing more, is rarely, and not without difficulty, perceived. The mode in which a train, in the order of place, is marked by the artifice of Predication, may be thus exemplified: "The house is on a hill; a lawn is in front; a stable is on the left hand; a garden is on the right; a wood is behind." It is not necessary, after the exposition of the preceding example, to exhibit the detail of the marking performed by these Predications. The reader can trace the sensations, the order of them, and the mode of the marking, according to the specimen which has just been exhibited.