Thinking that reality bottoms out in a fundamental level is a commonly held belief in both philosophy and physics. But Tuomas Tahko argues that alternatives to this foundational picture are equally compatible with the evidence. For example, we can interpret what the Standard Model of particle physics says about quarks in a coherentist light rather than a foundationalist one: since quarks depend on each other for their existence, quarks do not exist independently – something we normally think is true of fundamental entities. We should therefore not prejudge what the structure of reality might look merely based on our intuition that it might be foundational.

Philosophers and scientists alike often talk about “fundamentality” or the “fundamental level”. We might say that, fundamentally, everything is made of waves or that quantum field theory is as close to a fundamental theory as we currently have. More colloquially, we might say that ultimately everything is made of the fundamental “building blocks” of reality, whatever they may be – fields, particles, or something else. The thought is that these building blocks compose everything else, and so everything else depends on them, while these building blocks themselves do not depend on anything else because they are simple or have no further parts. The supposed fundamentality of a particle such as an electron is different from the supposed fundamentality of a theory such as quantum field theory. A fundamental theory may describe the “fundamentalia” – the fundamental entities – but as a representational device, the theory itself is not part of reality in the same way as the entities that it describes.