What we know is a drop, what we don't know is an ocean.

Our knowledge is a little island in a great ocean of nonknowledge.

Consciousness is the biggest mystery. It may be the largest outstanding obstacle in our quest for a scientific understanding of the universe.

The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexplicability.

Lo que sabemos es una gota de agua; lo que ignoramos es un océano.

We are more than all our knowledge. What we know confronts an infinitely encompassing unknown. The world is a mystery, and each of us is a mystery to himself.

Of what is significant in one's own existence one is hardly aware, and it certainly should not bother the other fellow. What does a fish know about the water in which he swims all his life?

We still do not know one thousandth of one percent of what nature has revealed to us

Translation: "What we know is not much. What we do not know is immense."

Very many maintain that all we know is still infinitely less than all that still remains unknown.

One thing about which fish know exactly nothing is water, since they have no anti-environment which would enable them to perceive the element they live in.

If our shallow, self-critical culture sometimes seems to lack a sense of the numinous or spiritual it's only in the same way a fish lacks a sense of the ocean.

We know so very little about this strange planet we live on, this haunted world where all answers lead only to more mystery.

There is much that science doesn't understand, many mysteries still to be resolved. In a Universe tens of billions of light-years across and some ten or fifteen billion years old, this may be the case forever. We are constantly stumbling on new surprises