  Over many years Peirce modified his views on the three types of arguments, sometimes changing his views but mostly extending them by expanding his commentary upon the original trichotomy.  Occasionally he swerved between one view and another concerning which larger class of arguments a particular instance or sub-type of argument belonged to. For example, he seemed to have some hesitation about whether arguments from analogy should be construed as inductions (arguments from a sample of the properties of things to a population of the properties of things) or abductions (conjectures made on the basis of sufficient similarity, which notion might not easily be analyzed in terms of sets of properties).