122 CORRELATION OF PHYSICAL FORCES. 



this planet oscillates about that of the freezing point of water, 

 as do the analogous zones of our planet. It is true, in this 

 we assume that the substance thus changing its state is water, 

 but, considering the many close analogies of this planet with 

 the earth, and the identity in appearance of these very effects 

 with what takes place on the earth, it seems a highly proba- 

 ble assumption. 



So it by no means necessarily follows, that because Venus 

 is nearer to the sun than the earth, that planet is hotter than 

 our globe. The force emitted by the sun may take a differ- 

 ent character at the surface of each different planet, and 

 require different organisms or senses for its appreciation. 

 Myriads of organised beings may exist imperceptible to our 

 vision, even if we were among them ; and we might be also 

 imperceptible to them ! 



However vain it may be, in the present state of science, 

 to speculate upon such existences, it is equally vain to assume 

 identity or close approximations to our own forms in those 

 beings which may people other worlds. From analogical 

 reasoning, or from final causation, if that be admitted, we 

 may feel convinced that the gorgeous globes of the universe 

 are not unpeopled deserts ; but whether the denizens of other 

 worlds are more or less powerful, more or less intelligent, 

 whether they have attributes of a higher or lower class than 

 ourselves, is at present an utterly hopeless guessing. 



Specific gravity and intelligence have no necessary con- 

 nexion. On our own planet five senses, and a mean density 

 equal to that of water, are not invariably associated with in- 

 tellectual or moral greatness, and the many arguments which 

 have been used to prove that suns and planets other than the 

 earth are uninhabited, or not inhabited by intellectual beings, 

 might, mutatis mutandis, equally be used by the denizens of 

 a sun or planet to prove that this world was uninhabited. 



Men are too apt, because they are men, because their 

 existence is the one thing of all importance to themselves, to 



