 Some philosophers were even more radically critical of operations like that performed by Cheselden. Mérian, for example, noticed that Cheselden’s observations, like all observations of blind people whose cataracts have been extracted, present difficulties because cataracts do not cause complete blindness and complete blindness cannot be cured. It could not be concluded from this that Molyneux’s problem could not be solved experimentally, however, for it could be maintained that patients operated upon for cataracts are directly relevant to the solution of it. They are unable to perceive form before they are operated upon, and the essential issue at stake when posing Molyneux’s problem is the ability to distinguish and name forms. This is a point of view which was taken by many philosophers.