Philosophy Concordance - online philosophical quotations

NOTHING is more free than the imagination of man; and though it cannot exceed that original stock of ideas furnished by the internal and external senses, it has unlimited power of mixing, compounding, separating, and dividing these ideas, in all the varieties of fiction and vision.

Its chief use is only to discover the constant and universal principles of human nature, by showing men in all varieties of circumstances and situations, and furnishing us with materials from which we may form our observations and become acquainted with the regular springs of human action and behaviour.

An interesting case of responding to something as something is that of a rat which has acquired the propensity to leap at panels with varieties of triangles painted on them.

On the absence of intermediate varieties in any one formation.

On the nature of extinct intermediate varieties; on their number.

On the absence of intermediate varieties at the present day.

Fertility of varieties when crossed and of their mongrel offspring not universal.

Absence or rarity of transitional varieties.

Struggle for life most severe between individuals and varieties of the same species; often severe between species of the same genus.

Many of the species of the larger genera resemble varieties in being very closely, but unequally, related to each other, and in having restricted ranges.