preposterous - Contrary to reason or common sense; utterly absurd or ridiculous.
When Sandy's stock broker called and suggested that he sell half his stocks because he felt the market was overvalued, Sandy thought the idea was preposterous - but it turned out that his stock broker was right.
nourish - To provide food or other substances necessary for growth, health, and good condition; also to support or promote the development of something (like ideas, feelings, or relationships).
She worked hard to nourish her creativity by painting every day.