It really comes down to parsimony, economy of explanation. It is possible that your car engine is driven by psychokinetic energy, but if it looks like a petrol engine, smells like a petrol engine and performs exactly as well as a petrol engine, the sensible working hypothesis is that it is a petrol engine.
Richard DawkinsThat there is a continuous link from humans to gorillas, with the intermediate species merely long dead, is beyond the understanding of speciesists. Tie the label Homo sapiens even to a tiny piece of insensible embryonic tissue, and its life suddenly leaps to infinite, incomputable value.... Self-styled pro-lifers, and others that indulge in footling debates about exactly when in its development a foetus becomes human, exhibit the same discontinuous mentality. Human, to the discontinuous mind, is an absolutist concept. There can be no half measures. And from this flows much evil.
Richard DawkinsWhat Francis [Collins] was just saying about Genesis was, of course, a little private quarrel between him and his Fundamentalist colleagues. It would be unseemly for me to enter in except to suggest that he'd save himself an awful lot of trouble if he just simply ceased to give them the time of day.
Richard DawkinsA gene might be able to assist replicas of itself that are sitting in other bodies. If so, this would appear as individual altruism but it would be brought about by gene selfishness.
Richard DawkinsReligion has been a powerful weapon in the hands of governments, in the hands of priests, in the hands of kings who have used it as a weapon to keep down the populace. It is a wonderful way of disciplining people and making them do what you want, to tell them that if they don't do what you want they will, for example, go to Hell.
Richard Dawkins