If the food selected by the appetite happens to be soup, or milk, or some mushy substance, get all the good taste out of it, doing all you can to accomplish this; for to get the taste out of food is an assurance of digesting it, and the pleasure it gives in the process of Nature's way of getting you to do the right thing in helping her to nourish yourself properly. Sip, taste, bite, press with the tongue against the roof of the mouth, the food in the mouth, not because of any suggestion of mine, but in response to the natural instinct to move it about and get out of it all the taste there is in it.
THIRD RULE
The moment appetite begins to slack up a bit, the moment saliva does not flow so freely as at first, the moment there is any degree of satisfaction of the appetite, stop eating!
You will have a return of appetite; you will have another chance to eat; appetite is beginning to have "that tired feeling" herself; be kind to her as she has been kind to you. Give her a rest! Give her a rest! Give yourself a rest! Rest is the antidote of "that tired feeling"! Therefore rest the appetite before it gets tired. Stop eating before you are overloaded.
Now, having learned how to do the right thing in eating so as never more to have "that tired feeling," don't begin to overdo. Don't bend backward too far. Don't ever overdo a good thing.
Be temperate; be deliberate. Be thoughtful; be forethoughtful; be forethoughtful without being fearthoughtful. Don't overdo chewing, for then you take away much of the pleasure; smother the psychic enjoyment of eating, and raise the very mischief again.
Just be natural, and know that being natural is being deliberate in enjoying the thing you are doing, for that is Nature's way.
To the above simple rules I will append a few recommendations which occurred to me and which I wrote while in a respiration calorimeter, an experience which I will relate in a subsequent chapter. This list of recommendations has since been included in the Instructions to the Medical Department of the United States Army, under the heading:
Method of attaining Economic Assimilation of Nutriment and Immunity from Disease, Muscular Soreness and Fatigue.