Sincerity is impossible, unless it pervades the whole being, and the pretence of it saps the very foundation of character. - James Russell Lowell
A cheerful heart is good medicine, but a broken spirit saps a person's strength - Jake Bible
As every divided kingdom falls, so every mind divided between many studies confounds and saps itself. - Leonardo da Vinci
Negative thinking saps strength. - Lailah Gifty Akita