Explanatory appeals to abstract ‘objects’ (numbers, moral values/principles, possible worlds etc…) are ubiquitous in philosophy, science, and everyday reasoning. Cicadas emerge in prime-number cycles because of number-theoretic advantages, lying is wrong because it violates the categorical imperative, Celtic FC would have won yesterday’s match had the referee been unbiased. Many philosophers take such claims’ explanatory usefulness to justify ontological commitment to the abstracta involved. Yet, by definition, abstracta are spatially and causally removed from the concrete world we seek to explain, raising a fundamental question: when, if ever, does explanatory appeal to abstracta genuinely license belief in their existence?
To answer this, I propose a methodological framework which distinguishes merely representative/heuristic explanations from metaphysically substantive ones. Two criteria structure the framework: ‘Basis’, scrutinises the reality of explanans and explanandum (independent of their inclusion in a particular explanation); and ‘Relevance’, assessing whether the explanans stands in an appropriate ontic-explanatory relation to the explanandum.
Applying this framework to case studies in mathematics, morality, and modality, I argue that explanatory appeals to abstracta systematically fail both criteria. Abstraction may be an indispensable representational tool, but abstracta themselves are never adequate explanans for why the concrete world truly is as it is.
It is generally accepted that agency requires materiality, since action must originate somewhere. In group agents, this implies that they are agential material objects rather than hovering, mind-like entities (Hess 2025). I argue that the material existence of group agents can be best explained by a Baker-style constitution relation (2000) between a group and its members, which is strictly non-mereological. First, I argue against Collins (2023) that her mereological account of group agents cannot successfully explain the relation between a group and its members because it fails to meet the non-transitivity desiderata of group agents. I subsequently show how this critique can be generalized to all mereological proposals (Hawley 2017; Hansson Wahlberg 2014). Secondly, I argue that the existing constitution accounts of group agents either fail to identify the correct material object from which the action of a group originates (Epstein 2015; Hindriks 2013; Uzquiano 2004) or account for it through mereological views of constitution (Harris 2020), which run into the same aforementioned problem. I conclude that a strictly non-mereological constitution account of the material existence of group agents is the most explanatorily successful since it is the only proposal that can meet the non-transitivity desideratum of group agents.
Ontological nihilism is a philosophical position that denies the existence of anything. The central concept of this position is nothingness. The origins of ontological nihilism can be found in the Old Testament, in the book of Genesis: God created the world from nothing. I argue that ontological nihilism is contradictory and cannot be true. I will try to prove that nothingness is a fiction and that being is everywhere, because nothingness does not exist. The fictional concept of nothingness arises when existence is separated from being. Then existence is nothing because it arises and disappears. But disappearing does not mean becoming nothing, and arising does not mean arising from nothing. Being contains arising, becoming, and disappearing, which do not exist separately from it. When we say that “God created the world out of nothing,” we mean that God existed before the world and created it out of nothing, that is, out of non-being. Now, let us consider the rephrased biblical statement: “God-being creates being out of non-being.” This statement is contradictory. God, as the very equivalent of being, can only create being from being, that is, from what is, and not from what is not, that is, from non-being.
