Every man is entangled in these difficulties, every rank is beset. For people without distinction draw the same conclusion from three arguments, than which none could be worse, namely for this the authority of our predecessors is adduced, this is the custom, this is the common belief; hence correct. But an opposite conclusion and a far better one should be drawn from the premises, as I shall abundantly show by authority, experience, and reason.

Should, however, these three errors be refuted by the convincing force of reason, the fourth is always ready and on everyman’s lips for the excuse of his own ignorance, and although he has no knowledge worthy of the name, he may yet shamelessly magnify it, so that at least to the wretched satisfaction of his own folly he suppresses and evades the truth.

Moreover, from these deadly banes come all the evils of the human race; for the most useful, the greatest, and the most beautiful lessons of knowledge, as well as the secrets of science and art, are unknown. But, still worse, men blinded in the fog of these four errors do not perceive their own ignorance, but with every precaution cloak and defend it so as not to find a remedy; and worst of all, although they are in the densest shadows of error, they think that they are in the full light of truth.

For these reasons they reckon that truths most firmly established are at the extreme limits of falsehood, that our greatest blessings are of no moment, and our chief interests possess neither weight not value. On the contrary, they proclaim what is most false, praise what is worst, extol what is most vile, blind to every gleam of wisdom and scorning what they can obtain with great ease. In the excess of their folly they expend their utmost efforts, consume much time, pour our large expenditures on matters of little or no use and of no merit in the judgment of a wise man. Hence it is necessary that the violence and banefulness of these four causes of all evils should be recognized in the beginning and rebuked and banished far from the consideration of science.

For where these three bear sway, no reason influences, no right decides, no law binds, religion has no place, nature’s mandate fails, the complexion of things is changed, their order is confounded, vice prevails, virtue is extinguished, falsehood reigns, truth is hissed off the scene. Therefore, nothing is more necessary of consideration than the positive condemnation of those four errors through the chosen arguments of wise men which shall prove irrefutable.”

As noted in the technical paper “Principles of Flight Test,” (AIAA-86-9742):
“In thirteenth-century England, Roger Bacon addressed the causes of error [the analysis above]. Although his four causes of error were written in response to a commission from Pope Clement IV rather than to meet the needs of twentieth-century flight test, his points are applicable.”

Independent of the original Latin and its 1928 translation* into what may now seem to be stilted or archaic English, Bacon’s analysis transcends time and technology.

Like the systems engineering process, the fundamentals are timeless. The failure of a product is a consequence of the creation of the product as opposed to something intrinsic in the product itself. “Modern” has seen the taming of steam and electricity and the invention of computers (circa 1890’s!), but the maxims are the same.

All successful projects follow the systems engineering process.  Some follow it deliberately. The others follow it eventually. Similarly, failures can be traced, ultimately and in keeping with an attribute of a fundamental truth, to the four root causes identified by Bacon. The intervening advances in technology have changed neither the basics deduced by Bacon or the fundamentals of systems engineering.

*The translation from the Latin is by Robert Belle Burke according to Moments of Discovery, Volume I, The Origins of Science by George Schwartz and Phillip W. Bishop, 1958, Basic Books Inc.