24 HEROES OF SCIENCE. 



But he was of use ; he was not merely a student of 

 the beauties of nature, but of the value of certain 

 plants to man in his pain and trouble, and he 

 founded the science of medical botany. 



Aristoteles, Theophrastus, Plinius, and Diosco- 

 rides are the men of mark who raised botany and 

 plant-learning out of their infancy and gave them 

 a youthful vigour. They placed the method of 

 learning, on its right basis. Instead of imagining 

 what was true, and then collecting and studying 

 plants to prove the correctness of the imagined 

 notion, they began in the opposite direction. They 

 strove to learn and discover facts, — truths, and then 

 reasoned upon them. Ignorant people, and those 

 men who have the minds of children, always like their 

 opinions and ideas better than facts, and especially 

 if the facts will not fit in with their notions. Such 

 people do not know how hard it is to find out the 

 truth in nature, how difficult it is for finite man to 

 comprehend infinite wisdom. This was as true 

 formerly as it is now, and hence the method of learn- 

 ing, taught by the earlier of those great men, was 

 opposed to the understandings of the majority of 

 their fellow men. They troubled the complacent 

 ignorance of the day, and were therefore perse- 

 cuted. Like brave men, they did not care for 

 persecution, knowing that they did not deserve the 

 wicked charges brought against them ; they perse- 

 vered, and not only enjoyed life much more than 

 their opponents, but led good and useful lives. 



The works of these men were studied by all the 



