The mental model theory (MMT) holds a deterministic view on causation regarding two aspects. From one aspect, MMT claims that the causal assertion “A causes B” implies that there are three temporally ordered possibilities: A and B, not A and B, not A and not B. On another aspect, MMT explicitly holds the view that “A causes B” indicates a necessary connection between A and B. Furthermore, MMT is strongly partial to the model of possibilities as the core meaning of causation but disregards other causal factors such as mechanisms, powers, or properties. In this paper, we showed that if MMT were to take its own principles seriously, then (a) the term “necessary connection” would be a vacuous concept, (b) it would confound causal necessity with logical necessity, or (c) the “mental model” would have little significance to causal determinism.