There has to be a measure of faith. That's what this business is all about: trusting in something that may never show up, that you have no concrete proof of.
Consciousness of myself, combined with complete ignorance of everything that does not fall within my sphere of thinking, is the most telling proof of my substantiality outside God, of my original existence.
There are some persons in this world, who, unable to give better proof of being wise, take a strange delight in showing what they think they have sagaciously read in mankind by uncharitable suspicions of them.
Do not consider it proof just because it is written in books, for a liar who will deceive with his tongue will not hesitate to do the same with his pen.
Such discoveries have led me, and other geologists, to reconsider the evidence previously derived from caves brought forward in proof of the high antiquity of Man.
The system is the work of art; the visual work of art is the proof of the System. The visual aspect can't be understood without understanding the system. It isn't what it looks like but what it is that is of basic importance.
Finally there are simple ideas of which no definition can be given; there are also axioms or postulates, or in a word primary principles, which cannot be proved and have no need of proof.
If leaders in the space program had at its beginning in the 1940s, pointed out the benefits to people on earth rather than emphasizing the search for proof of evolution in space, the program would have saved $100 billion in tax money and achieved greater results.
