850 Dynamic Theory. 



thus far are similar to the recollections we have of other men in regard 

 to the general essentials of existence. But we recollect further that 

 other men have finally died and this recollection we use to piece out the 

 recollections of Brown's unfinished history. As he is still living this 

 last part of the tale is of something still to come, and is therefore not 

 only a memory but also a prediction. Every act of ours involves a pre- 

 diction. The present act is an imitation of an act or parts of acts that 

 have been performed before. The recollection of the former act is the 

 guiding manual for the production of the present one, and it is predic- 

 tion as to the parts of the new act not yet carried out. It has been re- 

 marked by somebody that prediction is the highest form of reasoning. 

 The ability to tell what is to happen from data derived from the past 

 and present when it has been applied to unusual things, has often excited 

 admiration and wonder, and seemed almost to justify the apotheosis 

 which many have been willing to accord to Human Reason. The case 

 of the discovery of the position of the planet Neptune in 1847 by 

 the astronomers Le Terrier and Adams has often been pointed to as a 

 superlative example. The planet Uranus was discovered by accident. 

 The path of every planet is more or less disturbed by the influence of 

 the other planets of the system. When the orbit of Uranus was fully 

 marked out for it by the astronomers, due allowance having been made 

 for every influence they could think of within the solar system, it was 

 found by observation as it slowly plodded around its 84 year track, 

 that it deviated considerably from the caculated path. Having ex- 

 hausted inquiry within the then known system without finding the dis- 

 turbing element, the astronomers naturally concluded it must lie with- 

 out. And knowing that planets disturbed each other's orbits in the 

 manner in which this was disturbed, they concluded there must be 

 another planet outside of the orbit of Uranus. There was nothing at 

 all extraordinary in this conclusion except the magnitude and dignity of 

 the subject under consideration, although for that matter a man may 

 shoot a whale as easily as a squirrel if he is not afraid to try. If a 

 half-breed trapper finds one of his traps demoralized, the bait abstracted, 

 and the neighboring ground indented by strange and unfamilar tracks, 

 he comes to the conclusion that some new animal outside of the circle 

 of his acquaintance has been there and done the mischief, and he con- 

 trives some new apparatus by which to ensnare him, and perhaps lies in 

 wait all night besides. From a comparison of the operations of the 

 animals he knows with those of the unknown, he conjectures the char- 

 acter, nature, and strength of the latter. 



So our astronomers, being familiar with the performances of certain plan- 

 ets of their acquaintance, naturally attributed to an unknown planet, per- 

 formances which were every way like theirs, but which none of them were 



