THINGS ESSENTIAL TO BOTANICAL TEACHING 6 1 



habit of honest, disinterested observation, in discrimi- 

 native comparison, and in generalization in proper 

 logical degrees of truth. Every effort should be 

 made to cultivate a distrust and dislike for conclu- 

 sions based upon too scanty data ; a desire to go 

 always to the original sources of information ; and a 

 preference for the evidence of one's own senses 

 above any other source of knowledge. The teacher 

 may measure his success by the degree of mental 

 independence he arouses in his pupils. Speculation 

 should be encouraged, but not allowed to escape the 

 rigid control of facts. Every possible play should be 

 given to each student's individuality. The one who 

 has a taste and a knack for experiment should be 

 encouraged to become the class authority upon ex- 

 periment, and another the class artist, and so on. 

 Whenever possible, they should be allowed to feel 

 the pleasure and the stimulus of such authority. 



In judging the work done by the students, the 

 teacher should always remember that on the average 

 the most profitable point for which to aim is not the 

 maximum, but the optimum. It is a fact in educa- 

 tion, as in physiological and economic phenomena, 

 that the return for labor expended increases up to a 

 certain point, beyond which any further advance is made 

 at a disproportionately great cost. It is this best, or 

 optimum, point the teacher should in general seek ; and 

 he should not compel his students to follow refine- 



