Seen in retrospect, evolution as a whole doubtless had a general direction, from simple to complex, from dependence on to relative independence of the environment, to greater and greater autonomy of individuals, greater and greater development of sense organs and nervous systems conveying and processing information about the state of the organism's surroundings, and finally greater and greater consciousness. You can call this direction progress or by some other name.
Theodosius DobzhanskyEvolutionary plasticity can be purchased only at the ruthlessly dear price of continuously sacrificing some individuals to death from unfavourable mutations. Bemoaning this imperfection of nature has, however, no place in a scientific treatment of this subject.
Theodosius DobzhanskyThe living world is not a single array... connected by unbroken series of intergrades.
Theodosius DobzhanskyNature's stern discipline enjoins mutual help at least as often as warfare. The fittest may also be the gentlest.
Theodosius DobzhanskyNatural selection must be replaced by eugenical artificial selection. This idea constitutes the sound core of eugenics, the applied science of human betterment.
Theodosius Dobzhansky