If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family anatidae on our hands.

The difficulty with this conversation is that it's very different from most of the ones I've had of late. Which, as I explained, have mostly been with trees.

It is a well-known fact that those people who must want to rule people are, ipso facto, those least suited to do it... anyone who is capable of getting themselves made President should on no account be allowed to do the job.

The impossible often has a kind of integrity which the merely improbable lacks.

Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?

Time is an illusion. Lunchtime doubly so.

I love deadlines. I like the whooshing sound they make as they fly by.

I seldom end up where I wanted to go, but almost always end up where I need to be.

I may not have gone where I intended to go, but I think I have ended up where I intended to be.

The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair.

There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.There is another theory which states that this has already happened.

He hoped and prayed that there wasn't an afterlife. Then he realized there was a contradiction involved here and merely hoped that there wasn't an afterlife.

To give real service you must add something which cannot be bought or measured with money, and that is sincerity and integrity.

For a moment, nothing happened. Then, after a second or so, nothing continued to happen.

Life is wasted on the living.

Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the drug store, but that's just peanuts to space.

In the beginning the Universe was created. This has made a lot of people very angry and been widely regarded as a bad move.

Time is bunk.

We have normality. I repeat, we have normality. Anything you still can't cope with is therefore your own problem.

Flying is learning how to throw yourself at the ground and miss.

I'm spending a year dead for tax reasons.

You live and learn. At any rate, you live.

It is a mistake to think you can solve any major problems just with potatoes.

If somebody thinks they're a hedgehog, presumably you just give 'em a mirror and a few pictures of hedgehogs and tell them to sort it out for themselves.

He was a dreamer, a thinker, a speculative philosopher... or, as his wife would have it, an idiot.

The knack of flying is learning how to throw yourself at the ground and miss.

This must be Thursday. I never could get the hang of Thursdays.

Anyone who is capable of getting themselves made President should on no account be allowed to do the job.

In order to fly, all one must do is simply miss the ground.

A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.

If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family anatidae on our hands.

The mere thought hadn't even begun to speculate about the merest possibility of crossing my mind.

I don't believe it. Prove it to me and I still won't believe it.

I think fish is nice, but then I think that rain is wet, so who am I to judge?

It is a rare mind indeed that can render the hitherto non-existent blindingly obvious. The cry 'I could have thought of that' is a very popular and misleading one, for the fact is that they didn't, and a very significant and revealing fact it is too.

Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so.

The Guide is definitive. Reality is frequently inaccurate.

After ten years of word processing, I can't even do hand writing anymore.

Any man who can hitch the length and breadth of the galaxy, rough it, slum it, struggle against terrible odds, win through, and still knows where his towel is is clearly a man to be reckoned with.

As a child, I was an active Christian. I used to love the school choir and remember the carol service as always such an emotional thing.

Computers are still technology because we are still wrestling with it: it's still being invented; we're still trying to work out how it works. There's a world of game interaction to come that you or I wouldn't recognise. It's time for the machines to disappear. The computer's got to disappear into all of the things we use.

Cyberspace is - or can be - a good, friendly and egalitarian place to meet.

Every country is like a particular type of person. America is like a belligerent, adolescent boy; Canada is like an intelligent, 35-year-old woman. Australia is like Jack Nicholson. It comes right up to you and laughs very hard in your face in a highly threatening and engaging manner.

Hundreds of people who've never written before send in 'Dr. Who' scripts. They may have good ideas, but what they fail to realise is that writing for TV is incredibly complicated. They have no idea how difficult it is and what the financial commitment is.

I briefly did therapy, but after a while, I realised it is just like a farmer complaining about the weather. You can't fix the weather - you just have to get on with it.

I don't think anybody would argue now that the Internet isn't becoming a major factor in our lives. However, it's very new to us. Newsreaders still feel it is worth a special and rather worrying mention if, for instance, a crime was planned by people 'over the Internet.'

I find the difference, for me, between having no money and having quite a bit is that the bills get bigger. And that's it. The lifestyle doesn't change.

I find the whole business of religion profoundly interesting. But it does mystify me that otherwise intelligent people take it seriously.

I have rooms full of little dongly things and don't want any more. Half the little dongly things I've got, I don't even know what gizmo they're for. More importantly, half the gizmos I've got, I don't know where their little dongly thing is.