Analytical approaches have played an increasingly prominent role in Western music theory over the last two centuries. As a counterpart to predominantly descriptive methodologies, speculative thinking remained central to the music-theoretical projects of two Iberian authors, who sought not merely to explain musical phenomena but to induce new musical practices—often framed as pathways toward human regeneration or even unification with God. This paper argues that the speculative music theories of Sampaio Bruno and Juan Domínguez Berrueta can be productively understood through an epistemological–ontological framework, revealing both a shared speculative horizon and distinct modes of grounding tuning and Tonnetz theory beyond empirical validation.

In early twentieth-century Porto, Bruno proposed a heterodox tuning system rooted in the seventh harmonic, published as Théorie exacte et Notation finale de la Musique (1902). A few decades later in Salamanca, Berrueta elaborated a comparable tuning system (1927), likewise grounded in the seventh harmonic, supported by a three-dimensional acoustic Tonnetz structured around a fundamental tetraphonic harmony (1916). Berrueta also explicitly pointed to a lack of speculative thinking within contemporary music institutions.

Despite their familiarity with scientific positivism—evidenced by their ordering and use of experimental instruments and devices—both authors ultimately positioned their musical models outside immediate empirical validation. Berrueta claimed that his scientific theory of music “doesn't need the objective validation of a mechanical device that sounds the tetraphonic chords, nor the subjective validation of a more or less musical ear” (1927, 181; my translation). Similarly, Bruno argued that “it isn't our ear that must tune the music; on the contrary, it is the music that must tune our ear. [...] This means that it is not the senses that should impose themselves on reason, but rather reason that must ultimately purify the senses. [...] Such is the ultimate goal of exact music” (2011, 497; my translation).

The dialectic between scientific rationality, philosophical speculation, and religious faith thus constitutes a shared ground between these two figures. Berrueta expresses this position asserting that if “the regeneration of the scale does not find an echo in the masters of the art, we nevertheless trust that in the world of intelligence, much less than in that of matter, nothing is lost” (1927, 182; my translation). In Bruno's case, this stance is integrated teleologically into a broader meta-narrative of theodicy, where “God must be [...] a scientific notion. Theodicy will either be positive or it won't be” (1998, 250).

Bruno's and Berrueta's speculative music theories align with what Herman Pietersen (2014) describes as the “objectivist-empyrean” (Bruno) and “subjectivist-empyrean” (Berrueta) quadrants of an epistemological–ontological model of human thought. Applying this meta-theoretical framework provides new insight into their approaches to tuning, Tonnetz theory, and the speculative foundations of early twentieth-century Iberian music theory.

Berrueta, (1927). Teoría física de la música. Madrid:TV.

Bruno, (1998). A Ideia de Deus. Porto:LE.

Bruno, (1902). Theorie exacte et Notation finale de la Musique. Porto: TELT.

Bruno, (2011). Correspondência epistolar. Lisboa: INCM.

Pietersen, (2014). Christian Mysticism: A Meta-Theoretical Approach. Mediterranean Journal of Social Sciences, 5(16), 473.