A physician was troubled to remember on which side of the heart are the "mitral valves." As they are on the left side of the heart, he might have noticed that "mitral" ends with the letter "l," and that the word "left" begins with the letter "l"--as "l" belongs to both of these words, here would be a case of analysis. Such a device, however, could never be erected into a rule, for it is founded on accident only, and cannot be used in all cases. How much more vivid to many persons in this example is a Correlation, thus: "_Mitral valves_ ... mitred Abbots ... none left ... _left_."
To remember which of the University crews wears _dark_ blue and which _light_, we can note that the vowel "I" belongs alike to Cambridge and "Light" and is absent from Oxford and "Dark."
Take a case in Trigonometry--a _Complement_ is what remains after subtracting an angle from _one_ right-angle. Take 60 degrees from 90 degrees, and we have the complement 30 degrees--a _Supplement_ is what remains after subtracting an angle from two right-angles. Take 120 degrees from 180 degrees and we have the supplement 60 degrees. How to remember that "Complement" relates to one right-angle, and "Supplement" relates to two right-angles, is a difficulty for a poor memory. Looking at the accidents of the subject, we see that Supplement and two right-angles have a relation in this, that Supplement begins with S and two begins with _T_. S ... T. Hence we must remember that Supplement relates to _T_wo right-angles, and, of course, the word Complement to one right-angle.
Or to use the Synthetic Method: "_Complement_ (compliment) ... praise bestowed ... prize-winner ... won ... _one right-angle_" (_Complement_ completes right-angle ... _one_ ... _right-angle_) or "_Supplement_ ... supple ... bend double ... 'two double' ... _two right-angles_" (_Supplement_ ... added to ... more than one right-angle ... _two right-angles_).
I could give many other illustrations of the narrow scope of this Method of Accidents, though _genuine within that scope_, and how, in _all_ cases, by the Synthetic Method we can find in the facts _to be remembered_ the means of their recollection. One case more: In regard to memorising the statement that "the Posterior Nerve of the Spinal Column is Sensory, and the Anterior Nerve is Motor," using this Method of Accidents, "You observe that Posterior and Sensory go together, and that Anterior and Motor go together. The initial letters of Posterior and Sensory are P and S, and the initial letters of Anterior and Motor are A and M. By considering that A and M are in the upper part of the Alphabet and P and S are in the lower part of it, you will be sure to remember that Anterior is associated with Motor and Posterior with Sensory." I admit that the _first time_ one hears this elaborate method applied the novelty of the principle of it might make an impression; but, after that, the method would probably fail from its lengthy exposition; because it is difficult to retain the _steps of an argument_ in a weak Memory and therefore such a method cannot certainly act as a _Means for Aiding_ the Memory. How do I manage this case? By correlating Posterior to Sensory, thus: _Posterior_ ... Post-Mortem ... Insensible ... _Sensory_; or Anterior to Motor, thus: _Anterior_ ... Ant ... disturbed anthill ... commotion ... _Motor_; or _Anterior_ ... antediluvian ... rush of water ... water-power ... _Motor_. In uniting the two unconnected "Extremes" together by means of a _developed Analysis memorised_, the Natural Memory is aided in a very high degree.