Probability is expectation founded upon partial knowledge. A perfect acquaintance with all the circumstances affecting the occurrence of an event would change expectation into certainty, and leave nether room nor demand for a theory of probabilities.

Summary

This quote highlights the idea that probability is based on our limited understanding of all the factors that contribute to an event's outcome. If we were aware of every single detail influencing a specific occurrence, our expectations would be transformed into absolute certainty, thus removing the need for the study of probabilities. It emphasizes the role of uncertainty and the necessity of probability theories when we do not possess complete knowledge or control over the circumstances surrounding an event.

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