Abstract: A decision aiding tool uses quantifiable and knowable information as a proxy for generally unknowable information in order to provide basis for assessment of potential for achieving a goal. The knowable (non-specialist) information is linked to the goal to be assessed and to the unknowable (specialist) information via a decision tree. This is incorporated in a software toolkit for conversion of non-specialist information, elicited from a user, into specialist information. The toolkit presents to the user a series of Proxy Questions, each relating to aspects of the knowable information, and a number of possible Statements which may be selected in response. Each selected Statement is then quantified to provide a score and, with appropriate weighting, the scores are aggregated in accordance with the structure of the decision tree. This provides quantitative indicators of the unknowable information and of the potential for achieving the goal.