 The two virtues of thought that deal with what can be otherwise, i.e., what is contingent, are technê and phronêsis, craft and practical wisdom. Aristotle emphasizes the former, a disposition (hexis) with respect to making (poiêsis), is distinct from the latter, a disposition with respect to doing (praxis). First, technê is a disposition that produces something by way of true reasoning; it is concerned with the bringing into existence (peri genesin) of things that could either exist or not. The principle (archê) of these things is in the one who makes them, whereas the principle of those things that exist by necessity or by nature is in the things themselves (1140a1–20). For instance, carpentry makes this house and medicine produces health in a particular case. What is contingent is whether this house exists or whether health exits in this case. Since what it produces could exist or not, its products are one of the ways craft deals with the contingent. 