[Question] Why should EA care about rationality (and vice-versa)?

There’s a lot of over­lap be­tween the effec­tive al­tru­ism move­ment and the LessWrong ra­tio­nal­ity move­ment in terms of their mem­ber­ship, but each also has many peo­ple who are part of one group and not the other. For those in the over­lap, why should EA care about ra­tio­nal­ity and ra­tio­nal­ity care about EA?