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Can there be entities which have not been caused?

One obvious candidate would be the first state of the universe. Yet this matter is so strange that it would be rather breakneck to derive conclusions concerning criteria of existence from it.

Quantum physics may be interpreted as suggesting that the ventuation of states is determined by probability, or even by pure chance: in both cases, it would seem that those states, or the entities involved, do not eventuate by means of Causal Efficacy. Also, interactionist dualists about the mind may assume non-causal determination; there are several problems associated with the idea of mental causation; thus there is some reason to think that the influence the mind is supposed to exert on the body, according to interactionist dualism, is not causal.

Of course, interactionists dualists may, and some surely will, maintain that Causal Efficacy is still a valid criterion of existence in other areas of reality, such as within the physics of unanimated objects. The same holds, mutandis mutatis, for adherents of the interpretation of quantum physics just considered.