Dave Parnas Quotes

If the facts are contrary to any predictions, then the hypothesis is wrong no matter how appealing.

I'm a historian. The act of predicting the future discomfits me, in any event - and the bigger the prediction, the more distrusting I am.

When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

What do we believe? Why do we believe it?

I was aware, however, that telling at any point in my career could adversely affect my future career.

A thousand probabilities don't make one fact.

Nothing should be taken for granted, even if everybody believes it.

If two things don't fit, but you believe both of them, thinking that somewhere, hidden, there must be a third thing that connects them, that's credulity.

I try not to take any foolish chances, but there's just no way to play it completely safe and still do your job.

Belief is tricky because left to its own devices, it can court a kind of surety, an unquestioning allegiance that fears doubt and destroys difference.

Arguments from authority carry little weight – authorities have made mistakes in the past. They will do so again in the future. Perhaps a better way to say it is that in science there are no authorities; at most, there are experts.

Who can endure a doctrine which would allow only dentists to say whether our teeth were aching, only cobblers to say whether our shoes hurt us, and only governments to tell us whether we were being well governed?

The faithful believe that certain truths have been 'revealed.' The skeptics and secularists believe that truth is only to be sought by free inquiry and trial and error. Only one of those positions is dogmatic.

"As for that," said Waldenshare, "sensible men are all of the same religion." "Pray, what is that?" inquired the Prince. "Sensible men never tell."

Some guys-a lot of guys-don't believe what they are seeing, especially if it gets in the way of what they want to eat or drink or believe. Me, I don't believe in God. But if i saw him, I would. I wouldn't just go around saying, "Jesus, that was a great special effect." The definition of an asshole is a guy who doesn't believe what he's seeing.

Your ideas need not have anything to do with reality. Making conclusions is a sure way of not enhancing our perception.

Management is prediction.

It is a mysterious thing, the loss of faith-as mysterious as faith itself. Like faith, it is ultimately not rooted in logic; it is a change in the climate of the mind.

[...] intelligent people only have a certain amount of time (measured in subjective time spent thinking about religion) to become atheists. After a certain point, if you're smart, have spent time thinking about and defending your religion, and still haven't escaped the grip of Dark Side Epistemology, the inside of your mind ends up as an Escher painting.

I'm atheist because religion is a crutch, and only the crippled need crutches. I can get around perfectly well on my own two feet, and so can everyone else with a backbone and a grain of common sense.

Atheism is indeed the most daring of all dogmas . . . for it is the assertion of a universal negative.

I believe in religion against the religious; in the pitifulness of orisons, and in the sublimity of prayer.

It is absolutely safe to say that if you meet somebody who claims not to believe in evolution, that person is ignorant, stupid or insane (or wicked, but I'd rather not consider that).

As soon as we ask what faith is and what sort of mistreatment of faith causes doubt, we are led to the first major misconception about doubt-the idea that doubt is always wrong because it is the opposite of faith and the same thing as unbelief. What this error leads to is a view of faith that is unrealistic and a view of doubt that is unfair.