On Axiomatic Systems for Arbitrary Systems of Sentences
On Axiomatic Systems for Arbitrary Systems of Sentences
复制标题
论任意句子系统的公理系统
DOI:
10.1007/978-3-0346-0145-0_2
复制
发表时间:
2012
影响因子:
1.4
通讯作者:
J. Legris
中科院分区:
文献类型:
--
作者:
P. Hertz;J. Legris
Whenever a system of sentences is recognized to be valid, it is often not necessary to convey each and every sentence to memory; it is sufficient to choose some of them from which the rest can follow. Such sentences, as it is generally known, are called axioms. The choice of these axioms is to a certain degree arbitrary. One can ask, however, if the property of a system of sentences to have several axiom systems is interconnected with other remarkable properties, and if there are systematic approaches to find, as the case may be, that axiomatic system which contains the least possible number of sentences. In the following some thoughts shall be communicated, which might be useful as a pre-stage for the treatment of these or related problems. In fact the actual problem of interest is so entangled, that initially it seems appropriate to be content with an immense simplification: We only consider sentences of a certain type, sentences that we can write symbolically: (a1, . . . , an) → b and that can be expressed linguistically by formulations such as: If (a1, . . . , an) altogether holds, so does b. In addition, a second simplification will be introduced in the present first part, by only considering sentences of type a → b; however, we will liberate ourselves from this limitation in a following part. Further we assume rules according to which from certain sentences other ones follow: So, e.g., the validity of the sentences a → b, b → c should result in the holding of the sentence a → c. However, what is actually meant by such a sentence, what the symbol → means in the combination of characters a → b or the word ‘if’ in the corresponding linguistic formulation, does not have to be indicated here. At this point, it cannot be our task to lay out where we take the inference rules from, in what sense such sentences appear in ordinary life and which relation our question might have with the configuration of a scientific discipline. Also, the reason cannot be given here, why our considerations do not even begin to reach that level of generality which would be necessary if we wanted to reach by them a full understanding of the connection between mathematical or physical sentences and