Your assumptions are your windows on the world. Scrub them off every once in a while, or the light won't come in.
Treat with utmost respect your power of forming opinions, for this power alone guards you against making assumptions that are contrary to nature and judgements that overthrow the rule of reason.
Our minds have the need to know. When we don't know we make assumptions - they make us feel safer than not knowing. And we are pretty much always making assumptions.
Don Miguel Ruiz