 Steel (2010) has proposed that the Principle of Induction (understood as a rule which makes inductive generalisations along the lines of the Straight Rule) can be given a means-ends justification by showing that following it is both necessary and sufficient for logical reliability. The proof is an a priori mathematical one, thus it allegedly avoids the circularity of Hume’s second horn. However, Steel also does not see the approach as an attempt to grasp Hume’s first horn, since the proof is only relative to a certain choice of epistemic ends.