FUNDAMENTAL TRUTHS OF SCIENCE. 159 



Science and experience yield us information respecting 

 only the phenomena which exist or have existed ; their 

 mutual relations, and the changes of each. We have no 

 means of verifying by means of experience, nor by com- 

 parison or inference based upon experience, the idea that 

 the universe has or has not existed through infinite time, 

 or does or does not occupy infinite space ; and our beliefs, 

 therefore, respecting these questions are hypotheses, and 

 not real knowledge. Those ideas also cannot, therefore, be 

 properly called ' principles of science.' 



What, then, are these great principles which scientific 

 men value so highly ? They may be conveniently enume- 

 rated thus : 



1 . Universality of causation and of law. 



2. Coexistence of matter and energy. 



3. Conservation 



4. Persistency of phenomena (including that of rest 



and of motion, of form and of change of form). 



5. Universality of matter and of energy. 



6. motion. 



7. Dissipation of energy. 



8. Coincidence of change of matter and of its forces. 



9. Correlation of forces. 



10. Transformation 



11. Equivalency 



12. Transference of force. 



13. Concurrence of causes. 



14. Unequal action of causes, &c. 



By the proper application of these principles or general 

 truths, of combinations of them, or of minor principles 

 implicitly contained in them, the multitudinous and varied 

 phenomena of the universe may be (what we, by ordinary 

 latitude of speech, term) explained. For instance, a 

 knowledge of the law of action of gravity, and of the 



