150 COSMIC PHILOSOPHY. [n. I 



its cause," this view is in no way practically invalidated. 

 As Mr. Mill says, "Whether the cause and its effect be 

 necessarily successive or not, the beginning of a phenomenon 

 is what implies a cause, and causation is the law of the 

 succession of phenomena. ... I have no objection to define 

 a cause, the assemblage of phenomena, which occurring, 

 some phenomenon invariably commences, or has its origin 

 Whether the effect coincides in point of time with, or im- 

 mediately follows, the hindmost of its conditions, is imma- 

 terial. At all events it does not precede it ; and when we 

 are in doubt, between two coexistent phenomena, which is 

 cause and which is effect, we rightly deem the question 

 solved if we can ascertain which of them preceded the 

 other." i 



Secondly, invariableness of sequence is given in our ex- 

 perience of causation. Invariableness is the chief mark by 

 which we distinguish those sequences which are causal from 

 those sequences which are commonly termed accidental. 

 The well-known fallacy of post hoc, ergo propter hoc, upon 

 which are founded most of the current hygienic and thera- 

 peutic vagaries which claim to be upheld by experience, 

 aris is from the neglect of this essential distinction. It 

 lumps together all kinds of sequence under the general head 

 of causation. If drinking a cup of coffee is followed by 

 headache, or if a troublesome fit of indigestion ends after 

 taking a dose of patent medicine, it is rashly inferred that 

 the coffee caused the headache, or that the medicine cured 

 the indigestion. This is not legitimate induction. The 

 sequence may be accidental and not causal. The headache 

 may have been caused by eating hot risen biscuit, by inhaling 

 carbonic oxide sent up from the furnace, by overwork, or by 

 loss of sleep ; or it may be the premonitory symptom of a 

 typhoid fever due to imperfect drainage. The indigestion 

 may have been cured by a ride on horseback, or by a walk 

 1 Mill, Syst&m of Logic, 6th edit. vol. i. p. 384. 



