The most modest research worker at his bench, pushing a probe into a neuron to measure the electric response when a light is flashed, is enmeshed in … - Jacob Bronowski

My view is that diversity is the breath of life, and we must not abandon that for any single form which happens to catch our fancy – even our genetic fancy. Cloning is the stabilisation of one form, and that runs against the whole current of creation – of human creation above all. Evolution is founded in variety and creates diversity; and of all animals, man is most creative because he carries and expresses the largest store of variety. Every attempt to make us uniform, biologically, emotionally, or intellectually, is a betrayal of the evolutionary thrust that has made man its apex.

The brain cannot reach its inner conclusions by any logic of certainty. In place of this, the brain must do two things. It must be content to accept less than certain knowledge. And it must have statistical methods which are different in kind from ours, by which it reaches its acceptable level of uncertainty. By these means, the brain constructs a picture of the world which is less than certain yet highly interlocked in its parts.

Human beings can imagine situations which are different from those in front of their eyes... because they make and hold in their minds images for absent things.