 In  Section 1.2  we introduced the notion of a deductive consequence relation. One of the characteristic features of a deductive consequence relation is that adding more premises to a deductive argument allows you to derive all the same consequences as you could with fewer. In other words, for any sentences \(\alpha , \beta , \gamma\) in \(\mathbf{L}\): if \(\alpha \vdash \gamma,\) then \( \alpha\wedge \beta \vdash \gamma\).