Are the Effects of Use and Disuse Inherited? / An Examination of the View Held by Spencer and Darwin

The author examines the claim that acquired characters—changes produced by use and disuse—are transmitted to descendants, reviewing and critiquing the arguments and examples offered by prominent defenders of the idea. He evaluates anatomical and behavioral cases, addresses reports of inherited injuries and quasi-inheritance, and tests theoretical mechanisms such as pangenesis. The essay also considers the social and moral implications of accepting acquired inheritance. Through empirical scrutiny and logical analysis, the author finds the evidence unconvincing, deems the mechanism improbable and unnecessary for explaining variation, and concludes that reliance on such inheritance is misplaced.