I will analyse some properties of abduction that are essential from a logical standpoint. When dealing with the so-called 'inferential problem', I will opt for the more general concepts of input and output instead of those of premisses and conclusions, and show that in this framework two consequences can be derived that help clarify basic logical aspects of abductive reasoning: (i) it is more natural to accept the 'multimodal' and 'context-dependent' character of the inferences involved, (ii) inferences are not merely conceived of in the terms of the process leading to the 'generation of an output' or to the proof of it, as in the traditional and standard view of deductive proofs, but rather, from this perspective abductive inferences can b...