Errors with trials

Daniel Dennett's faith in the power of evolution goes too far ("Mind over matter", THES, April 30). In an article on "making mistakes" in How Things Are, he states his view even more explicitly: "Whatever the question or design problem is ... the only way to come up with the answer is to take some creative leaps in the dark and be informed by the results". Progress by trial and error should be avoided where possible. The main point of fundamental scientific research is to establish principles that are timeless and can be used to calculate future events (as well as explain past ones) and hence get designs near enough "right first time". Fortunately, Dennett is not designing bridges or aircraft.

John Sparkes Hemel Hempstead, Hertfordshire.