I have some quotes from various books I have read recently, that I would love to hear your thoughts on: Richard Feynman: "All these [chemical] rules were ultimately explained in principle by quantum mechanics, so that theoretical chemistry is in fact physics. On the other hand, it must be emphasized that this explanation is in principle. We have already discussed the difference between knowing the rules of the game of chess, and being able to play." Is the difficulty of not being able to play the game of chemistry, one that is related to lack of computational power? In other words, will we become better at playing the game as computational power continues to grow exponentially each year? Or is the difficulty a principal one, related to the clash between the quantum world and the classical world, requiring completely new theories to fill in the gap? Leonardo da Vinci: "No human investigation can be called real science if it can not be demonstrated mathematically." Do you sympathize with this statement? Would da Vinci say that biology is not a science, because we can not describe it mathematically? Do you believe all processes in the world, no matter how complex, must ultimately be possible to formulate by some mathematical formula, as da Vinci seems to suggest? Paul Davies: "Eddington's implicit boast of being the only person other than Einstein able to understand the general theory of relativity did not mean, I believe, that he and Einstein alone could visualize the revolutionary new concepts such as curved spacetime. But he may well have been among the first physicists to appreciate that in this subject true understanding comes only by relinquishing the need to visualize." Is this true for modern physics such as relativity theory and quantum mechanics? Do you have to give up the need to visualize, because we do not have any everyday experience of the concepts that are dealt with? If so, how can one gain true understanding of these theories? Or should one simply give up such an ambition, much like Davies seems to be suggesting? To quote Feynman once again, "If you think you understand quantum mechanics, you don't understand quantum mechanics." If you agree with Davies and Feynman, do you find the lack of understanding in modern physics frustrating, or do you think it makes the field even more exciting?