Weber relates explaining and understanding in this way in the opening chapter of Economy and Society. The italics are his and they point up some troublespots. Broadly, we are invited to contrast a level of meaning with a causal level and then combine them so as to arrive at 'sociological knowledge'. That sounds a very reasonable way to proceed; but it is easier said than done.

Part of the message is loud and clear. Actions cannot be explained by statistics alone. That would leave them 'either not intelligible at all or only imperfectly intelligible'. (M. Rouget's vote cannot be explained just by assigning him to a group of workers whose vote can be predicted with 80% probability.) So we must first traverse the level of meaning and then, to settle what is really going on, return to the causal level. But there is a crucial ambiguity. Is Weber saying that actions and their motives exist at the level of meaning but cannot be identified without the reassurance of statistics to deal with the problem of Other Minds? Or is he saying that actions have causes as well as meanings and we need both?