The paper discusses the question of why intervals, which are the main object of Interval Analysis, have exactly the form that we know well and habitually use, and not some other. In particular, we investigate why traditional intervals are closed, i.\,e. contain their endpoints, and also what is wrong with an empty interval. The second question considered in the work is how expedient it is to expand the set of traditional intervals by some other objects. We show that improper ("reversed") intervals and the arithmetic of such intervals (Kaucher complete interval arithmetic) are very useful from many different points of view.

翻译：本文讨论了为什么作为跨度分析主要对象的间隔有我们熟知的准确形式和习惯使用,而不是其他的。 特别是, 我们调查传统间隔关闭的原因, 即:\, 包含它们的终点, 以及空间隔有什么问题。 工作中考虑的第二个问题是, 扩大其他物体的传统间隔是否更方便。 我们从许多不同的观点来看, 不当( 逆差) 间隔和这种间隔的算术( 考切完整的算术) 非常有用 。