 Other approaches attempt to circumvent such problems by reductively defining the notion of commitment in terms of obligations to action and liability to error and/or vindication. Performance of a speech act or set of speech acts can commit an agent to a distinct content, and do so relative to some force. If P and Q jointly imply R, then my asserting both P and Q commits me to R. That is not to say that I have also asserted R: if assertion were closed under deductive consequence I would assert infinitely many things just by virtue of asserting one. By contrast, if I conjecture P and Q, then I am once again committed to R but not in the way that I would have been had I asserted P and Q. For instance, in the assertion case, once my further commitment to R is made clear, it is within the rights of my addressee to ask how I know that R holds; this would not have been an acceptable reply to my merely conjecturing P and Q. Developing this theme, let S be an arbitrary speaker, &lt;ΔlAl, …, ΔnAn, ΔB&gt; a sequence of force/content pairs; then: