“On the whole, however, the conclusions I have drawn from the proofs quoted may, I believe, safely be relied on. Assuredly they will not be disturbed either by the lays of a poet displaying the exaggeration of his craft, or by the compositions of the chroniclers that are attractive at truth's expense; the subjects they treat of being out of the reach of evidence, and time having robbed most of them of historical value by enthroning them in the region of legend.”

Source: Confessions of a Philosopher (1997), p. 346

Locus interview (2000)

Introduction
A Treatise of Human Nature (1739-40)
Context: Nothing is more usual and more natural for those, who pretend to discover anything new to the world in philosophy and the sciences, than to insinuate the praises of their own systems, by decrying all those, which have been advanced before them. And indeed were they content with lamenting that ignorance, which we still lie under in the most important questions, that can come before the tribunal of human reason, there are few, who have an acquaintance with the sciences, that would not readily agree with them. 'Tis easy for one of judgment and learning, to perceive the weak foundation even of those systems, which have obtained the greatest credit, and have carried their pretensions highest to accurate and profound reasoning. Principles taken upon trust, consequences lamely deduced from them, want of coherence in the parts, and of evidence in the whole, these are every where to be met with in the systems of the most eminent philosophers, and seem to have drawn disgrace upon philosophy itself.

Sons Come and Go, Mothers Hang in Forever (1976)

The Notebooks of Leonardo da Vinci (1883), I Prolegomena and General Introduction to the Book on Painting
Context: Though I may not, like them, be able to quote other authors, I shall rely on that which is much greater and more worthy — on experience, the mistress of their Masters. They go about puffed up and pompous, dressed and decorated with [the fruits], not of their own labours, but of those of others. And they will not allow me my own. They will scorn me as an inventor; but how much more might they — who are not inventors but vaunters and declaimers of the works of others — be blamed.

14 January letter to John Martin: 14, Correspondence between John Martin and William Smith O'Brien relative to a French invasion, 1861 https://books.google.com/books?id=uioenbWx30MC&pg=PA14,

On Property (24 April 1793)

Speeches, 20th Party Anniversary Address

The National Humane Review, Vol. 4–6, American Humane Association, 1916