Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
The supposed objectivity of science has come into question. Recent historical studies reveal instances in which scientific knowledge has not been strictly controlled by observation statements in turn established beyond reasonable doubt by rigorous scientific method. The scientific method has not always proven adequate; scientific observations have, at times, reflected personal biases.