The Commens Dictionary
Quote from ‘Minute Logic: Chapter II. Prelogical Notions. Section I. Classification of the Sciences (Logic II)’
Among the theoretical sciences [of discovery], I distinguish three classes, all resting upon observation, but being observational in very different senses.
Class II is philosophy, which deals with positive truth, indeed, yet contents itself with observations such as come within the range of every man’s normal experience, and for the most part in every waking hour of his life. Hence Bentham calls this class, coenoscopic. [CP 1.241n1: “Coenoscopic … from two Greek words, one of which signifies common – things belonging to others in common; the other looking to. By coenoscopic ontology, then, is designated that part of the science which takes for its subject those properties which are considered as possessed in common by all the individuals belonging to the class which the name ontology is employed to designate, i.e. by all individuals.” The Works of Jeremy Bentham, Edinburgh, 1843, viii, 83, footnote.] These observations escape the untrained eye precisely because they permeate our whole lives, just as a man who never takes off his blue spectacles soon ceases to see the blue tinge. Evidently, therefore, no microscope or sensitive film would be of the least use in this class. The observation is observation in a peculiar, yet perfectly legitimate, sense. If philosophy glances now and then at the results of special sciences, it is only as a sort of condiment to excite its own proper observation.
Next, passing to Class II, philosophy, whose business it is to find out all that can be found out from those universal experiences which confront every man in every waking hour of his life, must necessarily have its application in every other science. For be this science of philosophy that is founded on those universal phenomena as small as you please, as long as it amounts to anything at all, it is evident that every special science ought to take that little into account before it begins work with its microscope, or telescope, or whatever special means of ascertaining truth it may be provided with.