Skepticism is unbelief in cause and effect.

Talent alone cannot make a writer. There must be a man behind the book.

To laugh often and much ... this is to have succeeded. Probably not from Emerson: here's the full quotation and the story.

First be a good animal.

Defect in manners is usually the defect of fine perceptions. Men are too coarsely made for the delicacy of beautiful carriage and customs. It is not quite sufficient to good breeding, a union of kindness and independence.

Nature is upheld by antagonism. Passions, resistance, danger, are educators. We acquire the strength we have overcome.

The poet's habit of living should be set on a key so low that the common influences should delight him.