“The study of inbreeding depression seems to me especially important in the study of human abilities, because inbreeding depression indicates genetic dominance, and the presence and degree of dominance are related to natural selection for the trait in the course of its biological evolution. It was of great interest to me to discover, for example, that of the several ability factors that can be extracted from the various subtests of the Wechsler Intelligence Scale for Children, the one that shows the greatest susceptibility to inbreeding depression is the g factor (Jensen, 1983b). This finding indicates that one of our most widely used standard psychometric tests of intelligence yields scores that reflect some part of the variance in the biological intelligence that has developed in the course of human evolution.”

Source: Death Bringer

Price, G.R. (1995). "The nature of selection." Journal of Theoretical Biology 175:389-396 (written circa 1971)

Source: Letter to his daughter (1978), p. 15
Context: You cannot be big unless you are prepared to kiss the ground. You cannot defend the soil unless you know the smell of that soil. I know the smell of our soil. I know the rhythm of our rivers. I know the beat of our drums. The theories, the dogmas and the scripts stand outside the gates of history. The dominant factor is the aspiration of the people and the ability to seek total identification with it. Once the significance of the symphony is grasped, the lines fall into place, the dogmas and theories get legs to move in time to the majesty of that music. This does not mean that I am preaching pragmatism. There is a lot of expediency in pragmatism. I am trying to trace the roots of the problems, the genesis of the challenges, the cause of the struggle.

Source: Mendel's Principles of Heredity (1913), Chapter XV, p. 289.
Context: The concept of evolution as proceeding through the gradual transformation of masses of individuals by the accumulation of impalpable changes is one that the study of genetics shows immediately to be false. Once for all, that burden so gratuitously undertaken in ignorance of generic physiology by the evolutionists of the last century may be cast into oblivion. For the facts of heredity and variation unite to prove that genetic variation is a phenomenon of individuals.

Day One
Dialogue Concerning the Two Chief World Systems (1632)
Context: It always seems to me extreme rashness on the part of some when they want to make human abilities the measure of what nature can do. On the contrary, there is not a single effect in nature, even the least that exists, such that the most ingenious theorists can arrive at a complete understanding of it. This vain presumption of understanding everything can have no other basis than never understanding anything. For anyone who had experienced just once the perfect understanding of one single thing, and had truly tasted how knowledge is accomplished, would recognize that of the infinity of other truths he understands nothing.

Elements of Politics (3rd ed., 1908), Ch. 1: Scope and Method of Politics

On Max Weber's omission of medieval Christianity

Hence, people believed that genius and lunacy were intimately connected. Perhaps, nearly all of us “drive ourselves a little nuts” by virtue of creating stories that lead us to the illusion that we understand history, other people, causality, and life—when we don’t.
Source: Everyday Irrationality: How Pseudo-Scientists, Lunatics, and the Rest of Us Systematically Fail to Think Rationally (2001), Chapter 7, “Good Stories” (p. 125)