=1615.= The grandest achievement of the Hindoos and the one which, of all mathematical investigations, has contributed most to the general progress of intelligence, is the invention of the principle of position in writing numbers.--CAJORI, F. _History of Mathematics (New York, 1897), p. 87._ =1616.= The invention of logarithms and the calculation of the earlier tables form a very striking episode in the history of exact science, and, with the exception of the _Principia_ of Newton, there is no mathematical work published in the country which has produced such important consequences, or to which so much interest attaches as to Napier’s Descriptio. --GLAISHER, J. W. L. _Encyclopedia Britannica, 9th Edition; Article “Logarithms.”_ =1617.= All minds are equally capable of attaining the science of numbers: yet we find a prodigious difference in the powers of different men, in that respect, after they have grown up, because their minds have been more or less exercised in it. --JOHNSON, SAMUEL. _Boswell’s Life of Johnson, Harper’s Edition (1871), Vol. 2, p. 33._ =1618.= The method of arithmetical teaching is perhaps the best understood of any of the methods concerned with elementary studies.--BAIN, ALEXANDER. _Education as a Science (New York, 1898), p. 288._ =1619.= What a benefite that onely thyng is, to haue the witte whetted and sharpened, I neade not trauell to declare, sith all men confesse it to be as greate as maie be. Excepte any witlesse persone thinke he maie bee to wise. But he that most feareth that, is leaste in daunger of it. Wherefore to conclude, I see moare menne to acknowledge the benefite of nomber, than I can espie willying to studie, to attaine the benefites of it. Many praise it, but fewe dooe greatly practise it: onlesse it bee for the vulgare practice, concernying Merchaundes trade. Wherein the desire and hope of gain, maketh many willying to sustaine some trauell. For aide of whom, I did sette forth the first parte of _Arithmetike_. But if thei knewe how faree this seconde parte, doeeth excell the firste parte, thei would not accoumpte any tyme loste, that were emploied in it. Yea thei would not thinke any tyme well bestowed till thei had gotten soche habilitie by it, that it might be their aide in al other studies. --RECORDE, ROBERT. _Whetstone of Witte (London, 1557)._ =1620.= You see then, my friend, I observed, that our real need of this branch of science [arithmetic] is probably because it seems to compel the soul to use our intelligence in the search after pure truth. Aye, remarked he, it does this to a remarkable extent.