All things are possible until they are proved impossible — and even the impossible may only be so, as of now.

Everything is theoretically impossible, until it is done.

The only impossible thing is something to be impossible.

Everything is theoretically impossible, until it’s done. One could write a history of science in reverse by assembling the solemn pronouncements of highest authority about what could not be done and could never happen.

The impossible cannot have happened, therefore the impossible must be possible in spite of appearances.

Things always seem impossible until people do them.

We may, indeed, set it down as an absolute certainty, that many things are erroneously deemed impossible; for, till we know all the possible—and how far we are from that need not be insisted on—how can we know what is impossible?

There are many things that seem impossible only so long as one does not attempt them.

It always seems impossible until it's done.

It always seems impossible until it's done.

Only the impossible is worth attempting. In everything else one is sure to fail.

Nothing is impossible. Impossible just takes a bit longer.

nothing is impossible

The limits of possible can only be defined by going beyond them into the impossible.