Summary
This quote suggests that optimism can act as a stimulant for the heart, similar to how digitalis (a medication used for treating heart conditions) functions. In the context of failure, it implies that optimism can be a powerful tool to combat setbacks and adversity. It emphasizes that maintaining a positive outlook can provide the necessary motivation and energy to overcome failures and continue pursuing success. Just like how digitalis helps the heart perform better, optimism can rejuvenate and invigorate individuals during times of disappointment or failure.