Interval-valued computation is an unconventional computing paradigm. It is an idealization of classical 16-, 32-, 64- etc. bit based computations. It represents data as specific subsets of the unit interval – in this sense this paradigm is classified into the continuous space machine paradigm near to optical computing. In this paper we show the visual reasoning power of interval-valued computations, namely, we demonstrate that the decision process of quantified propositional formulae is fully representable in a natural visual form. Further, we give a temporal-logical interpretation of interval-valued computations.