 Tracz (2018) defends a reading that Helmholtz is a relationalist about perceptual properties, drawing on a related argument from Allais (2015) that transcendental idealism is a form of relationalism. “Helmholtz’s relationalism should be of interest to readers of Kant, for according to one of the main strands of interpretation, Kant’s transcendental idealism treats all properties that appear in perception as relational properties” (2018, 65). Moreover, “relationalism, particularly color relationalism, is alive in contemporary philosophy of perception (e.g., Chirimuuta 2015, Cohen 2009). Despite this, the history of relationalism is rarely thematized, so Helmholtz’s views provide some historical context of interest to present work in philosophy of perception” (Tracz 2018, 65).