LOGIC hypotheses shall have been tried, intelligent guessing may be expected to lead us to the one which will support all tests (P 6.530) This trust has to be presupposed at the outset, even though it may rest on no evidence But in fact the history of science shows such trust to be well founded: ‘it has seldom been necessary to try more than two or three hypotheses made by clear genius before the right one was found’ (P 7.220) Once the theory has been chosen, abduction is succeeded by deduction Consequences are derived from the hypothesis, experimental predictions that is, which will come out true if the hypothesis is correct In deduction, Peirce maintained, the mind is under the dominion of habit: a general idea will suggest a particular case It is by verifying or falsifying the predictions of the particular instantiations that the scientist will confirm, or as the case may be refute, the hypothesis under test It is induction that is the all-important element in the testing, and induction is essentially a matter of sampling Suppose a ship arrives in Liverpool laden with wheat in bulk Suppose that by some machinery the whole cargo be stirred up with great thoroughness Suppose that twenty-seven thimblefuls be taken equally from the forward, midships, and aft parts, from the starboard, center and larboard parts, and from the top, half depth and lower parts of her hold, and that these being mixed and the grains counted, four-fifths of the latter are found to be of quality A Then we infer, experientially and provisionally, that approximately four fifths of all the grain in the cargo is of the same quality (EWP 177) By saying that we draw the inference provisionally, Peirce means that if our experience be indefinitely extended, and every correction that presents itself be duly applied, then our approximation will become indefinitely close in the long run Inference of this kind, Peirce claims, rests on no postulation of matter of fact, but only on the mathematics of probability Induction thus described is quantitative induction: an inference from the proportion of a sample to the proportion of a population But there is another kind of induction that is important not only in science but in everyday life That is qualitative induction, when we infer from one or more observed qualities of an individual to other, unobserved qualities To illustrate this Peirce introduces us to the concept of the mugwump A mugwump, he tells us, has certain characteristics: 109