For almost every other qualification that contributes to his success, the teacher is in great degree dependent upon physical vigor. The better his health, the better will be his work. So wearing are his responsibilities that special effort on his part is required to preserve vigor and freshness. Often he becomes heart-weary and brain-weary, with the almost irresistible tendency to depression, coldness, or irritability. It is his duty not merely to resist such moods but to avoid their cause. He needs to keep the heart pure and sweet and trustful and sympathetic. In order to be always firm and calm and cheerful, he must preserve the strength of brain and nerve. 278 Since in his work quality is so much more important than quantity, he should guard against overlabor-- against attempting too much in his own line of duty; against accepting other responsibilities that would unfit him for his work; and against engaging in amusements and social pleasures that are exhausting rather than recuperative.

Da kvaliteten betyder så meget mere i hans arbejde end kvantiteten, bør han vogte sig for overanstrengelse for at forsøge at udrette alt for meget inden for sit eget arbejdsfelt; for at påtage sig andre forpligtelser, som kunne gøre ham mindre skikket til hans opgave, og for at tage del i fornøjelser og selskabelige adspredelser, der snarere er trættende end styrkende.