But I could be wrong.

- Carl Sagan

There is never only ONE of anything in nature.

- Carl Sagan

If we can't think for ourselves, if we're unwilling to question authority, then we're just putty in the hands of those in power. But if the citizens …

- Carl Sagan

Ask courageous questions. Do not be satisfied with superficial answers. Be open to wonder and at the same time subject all claims to knowledge, w…

- Carl Sagan

The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be…

- Carl Sagan

Nothing disturbs me more than the glorification of stupidity.

- Carl Sagan

Somewhere, something incredible is waiting to be known.

- Carl Sagan

Even through your hardest days, remember we are all made of stardust.

- Carl Sagan

The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars…

- Carl Sagan