This paper intends to critically consider the idea put forward by Johan Gamper that the principle of causal closure can be reconciled with the possibility of pluralism. This idea is based on redefining causal closure and on the introduction of so-called interfaces between the universes. By reconstructing and analyzing the author's argumentative steps, we will try to show that this approach is methodologically and explanatory unfounded. Firstly, this way of redefining the principle of causal closure is inconsistent with the very (...) reasons why this principle was introduced. Secondly, the proposed view does not bring the explanatory benefits it promises, that is, it cannot solve difficulties such as the problem of the first cause. Moreover, the position itself produces many additional concerns and perplexities that remain unresolved. The conclusion of our analysis is that certain aspects of the proposed position may be sustainable and plausible, but only if novel arguments should be offered. (shrink)