The design-rhetorical approach adopted in the Bern University of the Arts research projects can be characterized by five main hypotheses. First, it advocates the idea that effects of design artifacts can be analyzed by conceiving of design as a rhetorical process. To call a process “rhetorical” means that a piece of speech, or an artifact, is in general produced with a view to evoking certain reactions in an audience and that this is achieved by following specific rules or strategies that help bring about the intended effect. This does not mean that every design effect must be created consciously. Rather, effect orientation and (purposeful or tacit) rule application is supposed to be part of the basic ability of the designer as practitioner (Schneller 2010a). Just like speech, designed artifacts can be seen as attempts to catch the attention and goodwill of a public, to entertain, amuse, shock, or surprise, to create feelings, to influence opinions, values, or actions. However, design rules deal with the relation between the compositional structure and the immediate impulses presented in the design object. This way, they differ from effect studies in rhetoric and related fields such as advertising and consumer psychology where the primary focus is on conative effects (impact on volition, intentions, behavior, and actions) as well as long term effects such as attitude change, purchase behavior, memorization, or psychodynamic processes (Kazmi and Batra 2008; Giles 2003). Of course, some of the immediately perceptible effects of design objects can play a role in the determination of further conative and post-communicative effects. Although not sufficient for producing such secondary effects, design effects can provide “hints” pointing in their direction. A comfortable design might thus make a user or viewer feel comfortable and in doing so influence her purchasing decision, while a calm design might be suitable to provoke calming effects and consequently make viewers drowsy.
The second general hypothesis asserts that there is no such thing as effect-free or non-rhetorical design (Kinross 1985; Atzmon 2010; Schneller 2010b; Schneller/Scheuermann 2012). Every design affects or stimulates people, sometimes heavily, sometimes in subtle or perhaps almost unremarkable ways. Every act of shaping a design object involves a choice of shape, color, size, and proportion, and this choice will create differences in the appearance and impact of the object.
Third, the rhetorical dimensions logos, ethos, and pathos can be used to define three categories of visual effects. Similar to speech, design artifacts influence us not only on a rational (or functional) basis (logos), but also embody a character or act on our values (ethos) and stimulate our emotions (pathos).
Fourth, the relation between specific formal means and their visual (haptic and other) effects can be described in terms of design rules. Design effects are bound to laws of perception, viewing patterns, design traditions, movements, and fashions that shape and restrict the possibilities of the designer. An example for a design rule runs as follows: if you want to create a calm effect, use sans serif or roman type, low contrast, matte surfaces, open and symmetrical arrangements, and accentuate the horizontal. These rules can be actively or passively followed by designers in order to produce the effects intended with a designed object. It might seem that in advertising, the strategy is to break the conventions of seeing in order to surprise consumers rather than to simply follow design rules. Nevertheless, the sheer possibility of deviation reinforces the idea that there are rules at work. Many ads could perhaps be attributed to the use of second-order rules such as: if you want to catch attention or surprise, then break other rules such as “Be clear” or “Show things as they are.” The specific use of formal and semantic deviations is indeed a typical rhetorical phenomenon. Visual rhetorical figures and tropes such as hyperboles, metaphors and ellipses are defined by specific deviations from the norm, for example, addition, repetition, omission, or transformation (Ehses 1986).
Fifth, there is an overall rhetorical principle that guides the range of possible deviations, called the decorum or aptum. It controls the adequacy of effects and measures rule application (or breach) relative to the context of a design artifact.