'Food to be kept warm for the Sabbath must not be put into oil-dregs, manure, salt, chalk, or sand, whether moist or dry, nor into straw, grape-skins, flock, or vegetables, if these are damp, though it may if they are dry. It may, however, be put into clothes, amidst fruits, pigeons' feathers, and flax tow. R. Jehudah declares flax tow unallowable and permits only coarse tow.'"[10] Following his rule out, step by step, with unflinching loyalty, into these ridiculous consequences, the Pharisee had entirely lost the power of seeing that they were ridiculous, and was well content to believe, with Jehudah, that the difference between keeping food warm in coarse tow and in flax tow was the difference between life and death. This _reductio ad absurdum_ of legalism is exactly paralleled, in many of our elementary schools, in the answers to arithmetical questions given by the children. The "Fifth Standard" boys who told their inspector, as an answer to an easy problem, that a given room was five shillings and sixpence wide, had followed out their rule--they had unfortunately got hold of a wrong rule--step by step, till it led them to a conclusion, the intrinsic absurdity of which they were one and all unable to see.[11] There are many elementary schools in England in which a majority of the answers given to quite easy problems would certainly be wrong, and a respectable minority of them ludicrously wrong. Nor is this to be wondered at; for though the types of problems that can be set in elementary schools are not numerous, to provide his pupils with the by-rules which shall enable them in all, or even in most cases, to determine which of the recognised rules are appropriate to the given situation, passes the wit of the teacher. But if the helplessness of so many elementary scholars in the face of an arithmetical problem is lamentable, still more lamentable is the fact that the scholar is seldom met with who, having given an entirely wrong answer to an easy problem, is able to see for himself that, whatever the right answer may be, the answer given is and must be wrong. So fatal to the development of the arithmetical sense is the current worship of the rule for its own sake, and so deadly a narcotic is the conventional arithmetic lesson to all who take part in it! It is not in the arithmetic lesson, then, that provision is ordinarily made for the development of a sense, or perceptive faculty, through the medium of self-expression on the part of the child. On the contrary, the very _raison d'etre_ of the arithmetic lesson, as it is still given in many schools, is to destroy the arithmetical sense, and make the child an inefficient calculating machine, which, even when working, is too often inaccurate and clumsy, and which the slightest change of environment throws at once and completely out of gear.