1) I do indeed deny you need to know the exact mechanism of toxicity to model it. In fact, having any kind of quantitative model is better than the qualitative

1) I do indeed deny you need to know the exact mechanism of toxicity to model it. In fact, having any kind of quantitative model is better than the qualitative A increases/decreases B stuff that is usual. The reason being that it is too vague and many explanations can account for such an observation. 2) But please, let us skip the philosophy and talk directly about this topic, because that argument is not even necessary. It sounds to me like you do not believe that double strand breaks can lead to cell death and growth arrest? You find this implausible? I am really surprised that this is an objection.