Instead of the exquisite simplicity and clearness of Abernethy's views, so far as he had gone, being carefully studied, and with a view to the _extension_ of them beyond those limits which his time, his opportunities, and his caution had assigned to them; instead of examining into, and testing, the practical value of the deducible, and, in fact, necessary sequences, on views of which he had demonstrated the truth and value; practice appears to have taken a retrograde movement. He who would advance even as far as Abernethy, is in danger of being regarded as crotchety or peculiar; whilst any who should strive by a more careful examination of his views to render their practical application more definite and analytical, must be prepared to be looked on simply as an enthusiast. This has, indeed, been the case more or less in all sciences from the earliest times. The _facts_ which conduct us to a true interpretation of the _laws_ in obedience to which they occur, have been always before us; the very same facts on which, as Professor Whewell[29] observes, we have raised the stately structure of modern science. Butler[30] had before made a similar remark. Poets too, as even the motto to our chapter shows, have held the same sentiment; what everybody _knows_, how few _consider_! Neither Copernicus nor Galileo altered or invented _facts_. Those they _observed_! what they _discovered_, were conclusions interpreting the true relations of them. Bodies fell to the earth, and the crystal rain-drop had shown the composite nature of light in the beautiful colours and wonderful illustrations of the rainbow, ages before Newton discovered the true explanation of the one, and the great law exemplified in the other.