Surely this is a great part of our dignity . . . that we can know, and that through us matter can know itself; that beginning with protons and electrons, out of the womb of time and the vastness of space, we can begin to understand; that organized as in us, the hydrogen, the carbon, the nitrogen, the oxygen, those 16 to 21 elements, the water, the sunlight — all, having become us, can begin to understand what they are, and how they came to be.— George Wald (1964)
The more we learn, the more we are — or ought to be — dumbfounded.— Lewis Thomas (1983)
Image: Plant cells with visible chloroplasts from a moss Plagiomnium affine, Kristian Peters. There can be around 50 chloroplasts in a typical plant cell. A square millimetre of leaf may contain 450,000 to 800,000 chloroplasts.