The implications of persistent and widening global current account imbalances have been at the center of policy debates over the last half decade. While the concerns subside each year, as a rapid unraveling of the imbalances fails to materialize, the intellectual challenge of determining what drives these imbalances remains. To the extent that some policymakers view the configuration of imbalances to be undesirable, a salient question remains what policies would cause those imbalances shrink.
These imbalances are large. The U.S. deficit was 6.5% of GDP, while China’s surplus was 9.1%, with balances in the next two years projected at 10%. The rest of the Developing Asian region is running an average current account surplus of 5.4%. Finally, the sustained elevation in oil prices has added oil exporters to the list of surplus countries. Figure 1 highlights the lopsided nature of imbalances, with the U.S. deficit primarily financed by East Asia and the Middle East.
Compared to temporal logics, modal logics of space have received very little attention. I can see two reasons for this. First, temporal logic has its roots in the semantics of natural language; here, the notion of tense naturally leads to an extension of classical logics with temporal modal operators. In most familiar languages spatial concepts seem to play a less pervasive role, notwithstanding the many expressions that could be interpreted as spatial modalities. Also, the development of temporal logic has been boosted by concerns from computer science, in the context of program specification and verification. Here temporal properties are of greater interest than spatial ones.
A second reason is perhaps that it is more evident which ontologies to employ when formalizing the notion of time; apart from some notable exceptions, the standard temporal structure consists of a set of time points together with some kind of ordering of these points. When devising a formal model of space we seem to be faced with a far greater choice. Even if we decide to restrict ourselves to points as spatial objects, there are a great number of interesting relations to consider, such as nearness, collinearity, betweenness or equidistance. But also, the restriction to points as the sole entities of the mathematical model is more debatable than in the temporal case. For, space is inhabited by various kinds of things, such as lines, spheres, planes, poyhedra, etc.
The issue of safety of Chinese herbal remedies must be paramount in the mind of practitioners for two reasons. First and foremost, because, as practitioners, we must strive to give patients the best possible care and minimize possible side-effects and adverse reactions; secondly, we need to be seen to practise in a professional and responsible manner that ensures the maximum safety if we are to satisfy potential regulatory authorities. There are more and more negative reports regarding the alleged toxicity of herbal remedies (many of them misguided or plainly wrong) and we need, as practitioners, not only to practise in the safest way possible, but also to be seen to do so.
