A rock or stone is not a subject that, of itself, may interest a philosopher to study; but, when he comes to see the necessity of those hard bodies, in the constitution of this earth, or for the permanency of the land on which we dwell, and when he finds that there are means wisely provided for the renovation of this necessary decaying part, as well as that of every other, he then, with pleasure, contemplates this manifestation of design, and thus connects the mineral system of this earth with that by which the heavenly bodies are made to move perpetually in their orbits. It is not, therefore, simply by seeing the concretion of mineral bodies that a philosopher is to be gratified in his his intellectual pursuit, but by the contemplation of that system in which the necessary resolution of this earth, while at present it serves the purpose of vegetation, or the fertility of our soil, is the very means employed in furnishing the materials of future land. It is such a view as this that I have endeavoured to represent in the theory which I have given. I have there stated the present situation of things, by which we are led to perceive a former state; and, from that necessary progress of actual things, I have concluded a certain system according to which things will be changed, without any accident or error. It is by tracing this regular system in nature that a philosopher is to perceive the wisdom with which this world has been contrived; but, he must see that wisdom founded upon the aptitude of all the parts to fulfil the intention of the design; and that intention is to be deduced from the end which is known to be attained. Thus we are first to reason from effect to cause, in seeing the order of that which has already happened; and then, from those known causes, to reason forwards, so as to conceive that which is to come to pass in time. Such would be the philosophy of this earth, formed by the highest generalisation of phenomena, a generalisation which had required the particular investigation of inductive reasoning.