Francis Crick Quotes

A person's mental activities are entirely due to the behavior of nerve cells, glial cells, and the atoms, ions, and molecules that make them up and influence them.

What is found in biology is mechanisms, mechanisms built with chemical components and that are often modified by other, later, mechanisms added to the earlier ones. While Occam's razor is a useful tool in the physical sciences, it can be a very dangerous implement in biology. It is thus very rash to use simplicity and elegance as a guide in biological research. While DNA could be claimed to be both simple and elegant, it must be remembered that DNA almost certainly originated fairly close to the origin of life when things were necessarily simple or they would not have got going. Biologists must constantly keep in mind that what they see was not designed, but rather evolved. It might be thought, therefore, that evolutionary arguments would play a large part in guiding biological research, but this is far from the case. It is difficult enough to study what is happening now. To figure out exactly what happened in evolution is even more difficult. Thus evolutionary achievements can be used as hints to suggest possible lines of research, but it is highly dangerous to trust them too much. It is all too easy to make mistaken inferences unless the process involved is already very well understood.

There is no scientific study more vital to man than the study of his own brain. Our entire view of the universe depends on it.

It is not easy to convey, unless one has experienced it, the dramatic feeling of sudden enlightenment that floods the mind when the right idea finally clicks into place. One immediately sees how many previously puzzling facts are neatly explained by the new hypothesis. One could kick oneself for not having the idea earlier, it now seems so obvious. Yet before, everything was in a fog.

An honest man, armed with all the knowledge available to us now, could only state that in some sense, the origin of life appears at the moment to be almost a miracle, so many are the conditions which would have had to have been satisfied to get it going.

An honest man, armed with all the knowledge available to us now, could only state that in some sense, the origin of life appears at the moment to be almost a miracle, so many are the conditions which would have had to have been satisfied to get it going. But this should not be taken to imply that there are good reasons to believe that it could not have started on the earth by a perfectly reasonable sequence of fairly ordinary chemical reactions. The plain fact is that the time available was too long, the many microenvironments on the earth's surface too diverse, the various chemical possibilities too numerous and our own knowledge and imagination too feeble to allow us to be able to unravel exactly how it might or might not have happened such a long time ago, especially as we have no experimental evidence from that era to check our ideas against. Perhaps in the future we may know enough to make a considered guess, but at the present time we can only say that we cannot decide whether the origin of life on earth was an extremely unlikely event or almost a certainty — or any possibility in between these two extremes.

Philosophers have been especially concerned with the problem of consciousness—for example, how to explain the redness of red or the painfulness of pain. This is a very thorny issue. The problem springs from the fact that the redness of red that I perceive so vividly cannot be precisely communicated to another human being, at least in the ordinary course of events. If you cannot describe the properties of a thing unambiguously, you are likely to have some difficulty trying to explain these properties in reductionist terms.

Christianity may be OK between consenting adults in private but should not be taught to young children.

Only gradually did I realize that this lack of qualification could be an advantage. By the time most scientists have reached age thirty they are trapped by their own expertise. They have invested so much effort in one particular field that it is often extremely difficult, at that time in their careers, to make a radical change. I, on the other hand, knew nothing, except for a basic training in somewhat old-fashioned physics and mathematics and an ability to turn my hand to new things. I

The hallmark of a successful theory is that it predicts correctly facts that were not known when the theory was presented, or, better still, which were then known incorrectly. A good theory should have at least two characteristics: it should be in sharp contrast to at least one alternative idea and it should make predictions which are testable.

Big questions get big answers.

If for example I had some idea, which as it turned out would be quite wrong, was going off of the tangent, Watson would tell me in no uncertain terms this was nonsense, and vice-versa. If he would have some idea I didn't like, and I would say so, this would shake his thinking about, and draw him back again. And in fact it is one of the requirements for collaborations of this sort, is you must be perfectly candid, one might almost say rude, to the person you're working with. It's useless working with somebody who is either much too junior than yourself or much too senior because then politeness creeps in. And this is the end of all real collaboration in science (giggles).

Both of us had decided, quite independently of each other, that the central problem in molecular biology was the chemical structure of the gene.

Whatever has a beginning must have an ending.

It is essential to understand our brains in some detail if we are to assess correctly our place in this vast and complicated universe we see all around us.