IMMEDIATE REASONING. The simplest form of reasoning is that known as "immediate reasoning," by which is meant reasoning by directly comparing two judgments without the intervention of the third judgment, which is found in the more formal classes of reasoning. This form of reasoning depends largely upon the application of the Three Primary Laws of Thought, to which we have referred in a previous chapter. It will be seen that _if_ (_a_) a thing is always itself, then (_b_) all that is included in it must partake of its nature. Thus, the bird family has certain class characteristics, therefore by immediate reasoning we know that _any_ member of that family must possess those class characteristics, whatever particular characteristics it may have in addition. And we likewise know that we cannot attribute the _particular_ characteristics, as a matter of course, to the other members of the class. Thus, though all sparrows are birds, it is not true that all birds are sparrows. "All biscuits are bread; but all bread is not biscuit." In the same way we know that a thing cannot be bird and mammal at the same time, for the mammals form a not-bird family. And, likewise, we know that everything _must_ be either bird or not bird, but that being not bird does not mean being a mammal, for there are many other not-bird things than mammals. In this form of reasoning distinction is always made between the _universal_ or general class, which is expressed by the word _all_, and the _particular_ or individual, which is expressed by the word "some." Many persons fail to note this difference in their reasoning, and fallaciously reason, for instance, that because _some_ swans are white, _all_ swans must be so, which is a far different thing from reasoning that if _all_ is so and so, then _some_ must be so and so. Those who are interested in this subject are referred to some elementary text-book on logic, as the detailed consideration is too technical for consideration here. REASONING BY ANALOGY. Reasoning by analogy is an elementary form of reasoning, and is the particular kind of reasoning employed by the majority of persons in ordinary thought. It is based upon the unconscious recognition by the human mind of the principle which is expressed by Jevons as: "_If two or more things resemble each other in many points, they will probably resemble each other in more points._" The same authority says: "Reasoning by analogy differs only in degree from that kind of reasoning called '_generalization_.' When _many things_ resemble each other in a _few properties_, we argue about them by generalization. When a _few things_ resemble each other in _many properties_, it is a case of analogy."