Preface to the Treatise on VacuumBlaise Pascal

Pascal wrote this preface around 1651, in the context of his barometric experiments that confirmed the existence of the vacuum against Aristotelian orthodoxy. The short text makes an argument that reaches well beyond physics: in the sciences of nature, authority counts for nothing, and only experiment and reason can settle questions.

Pascal distinguishes two domains of knowledge. In theology and morals, authority is supreme, because the truths of revelation exceed what reason can discover on its own. In the natural sciences, the situation is reversed. Here, reliance on ancient authority is not humility but intellectual servitude. Aristotle and the ancients deserve respect for what they discovered, but their conclusions are starting points, not endpoints. Each generation stands on the shoulders of those before it and sees further.

The preface articulates one of the earliest explicit statements of the idea of scientific progress. Humanity as a whole, Pascal argues, can be regarded as a single person who never ceases to learn. What the ancients knew was the childhood of knowledge. To treat their opinions as final is to mistake the beginning for the conclusion. The text is brief, forceful, and surprisingly modern in its insistence that the sciences advance by overthrowing their predecessors rather than by deferring to them.