Session 1 of 37

How Do You Know?

CHEM 125a · Lecture 1

Video

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Notes

My notes for this session go here.

AI summary

McBride opens the course with its guiding question: How do you know? He lays out four ways people come to believe something — divine authority, human authority, direct experiment, and logic — and argues that science sets authority aside and follows the evidence. Faraday, who taught himself chemistry from a book, and Feynman — "science is the belief in the ignorance of experts" — stand in for that skepticism.

Most of the lecture traces how this outlook took hold in the 1600s. Francis Bacon pushed inductive experiment over inherited Aristotelian argument, inspiring the Royal Society and its motto Nullius in Verba — take nobody's word for it. A "crucial experiment" settles a choice between rival explanations, as when Newton's prism showed a beam is split into colours, not painted by the glass.

It closes on the physics behind bonding: Boyle's springy air and Hooke's law, where restoring force grows with displacement and stored energy with its square — the model for the bonds to come.

AI questions

  1. What are the specific requirements for participating in the course Wiki, and why is there a strict 36-hour deadline for completing assigned entries?
  2. According to the instructor and Louis Pasteur, what is the "mind's first step toward discovery," and how does this contrast with the popular "Eureka" moment?
  3. The lecture identifies four ways of knowing. Which two are explicitly ignored by science, and which two form the basis of the scientific method?
  4. How did Francis Bacon's "Great Restoration" (Instauratio Magna) propose to change the way knowledge was developed compared to the Aristotelian deduction taught in universities at the time?
  5. What is the meaning of the Royal Society's motto, Nullius in Verba, and how does it relate to Richard Feynman's assertion that "science is the belief in the ignorance of experts"?
  6. Define what Francis Bacon called a "crucial experiment" (Experimentum Crucis). How did Isaac Newton use a prism to perform such an experiment regarding the nature of light?
  7. Why is Samuel Pepys presented as a model for success in this course, and what specific attitude toward "knowing" did he demonstrate in his correspondence with Newton?
  8. In the 17th century, why was the study of chemistry considered vital to the interests of the British government and the Royal Society, specifically regarding national strength?
  9. Why did Robert Hooke publish his theory of springs as an anagram (ceiiinosssttuv), and what was the unscrambled Latin phrase and its scientific meaning?
  10. Based on Hooke's Law, what is the mathematical relationship between force and the distortion of a spring, and how is this relationship represented in terms of potential energy?