 (3) There is another sense in which both  principles—IMP  and  CON—place  excessive demands on agents whose resources are limited. Consider the following example. Suppose I believe the axioms of Peano arithmetic. Suppose further that a counterintuitive arithmetical proposition that is of great interest to me is entailed by the axioms, but that its shortest proof has more steps than there are protons in the visible universe. According to  IMP,  I ought to believe the proposition in question. However, if the logical “ought” implies “can” (relative to  capacities even remotely like our own),  IMP  cannot be correct. An analogous objection can be leveled at  CON.  An agent may harbor an inconsistent belief set, yet detecting the inconsistency may be too difficult for any ordinary agent. We may summarize these objections under the label Objection from Excessive Demands.