Who does Cassandra Nightingale quote when she says that 'Present opportunities are not to be neglected They rarely visit us twice' in the 'Good Witch' films and series?

Cassandra Nightingale quotes the author and philosopher William James when she says, "Present opportunities are not to be neglected. They rarely visit us twice." This quote emphasizes the importance of seizing the moment and making the most of opportunities as they arise. Cassandra's character often embodies themes of wisdom and encouragement, reflecting the idea that one should act decisively when chances present themselves.