Recently, the so-called evidence-based knowledge has had an increasingly dominating role in societal decision-making. With the sustainability and climate change debates, and the related demands on impact assessments, its role has been heightened in spatial planning,1 too (e.g. Davoudi, 2012; Krizek et al., 2010). However, in planning, the hegemony of evidence-based knowledge is problematic, as planning is largely about coping with the yet unknown future; that of which we cannot have evidence. This is especially true for strategic spatial planning that incorporates the methods of scenario planning (Albrechts, 2005; Zegras and Rayle, 2012). The evidence-based approach addresses the future as a continuation of the existing and known development paths. While, in scenario planning, there is indeed a need to project the future implications of the present development paths, we also need an ability to imagine such development trajectories, of which we do not have evidence yet, but which might emerge in the future.