If you need proof, open all the borders on Earth and see what happens.

He needed only proof, for the truth was so extraordinary.

Other sites offer help to people who need proof that they are working.

Now she needed proof that there really was a God.

But the lawyers needed proof that this was a company policy.

We're going to need proof before we can make any public accusations.

If you still need more proof, look at the girl's neck.

He needed only a missing piece or two, and, of course, legal proof.

And if I had needed proof, it was there to be seen after.

As in love, words are not enough: we need action and proof.