title: What the Tortoise said to Achilles.
abstract: Practitioners and investigators often view clinical trials from very different perspectives-the former in terms of individuals and the latter in terms of groups. The following whimsical dialogue highlights the philosophical foundations of these contrasting perspectives and illustrates their potential impact on patient care and public policy. The title alludes to a piece by Lewis Carroll regarding Zeno's paradox, purportedly proving that the fleet-footed Achilles cannot outrun the plodding Tortoise in a foot race.
authors.forename: George A
authors.initials: GA
authors.lastname: Diamond
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kaul
mesh_terms: D002986:Clinical Trials as Topic; D006801:Humans