XXII–LII. There are many forms of privileged instances: (One) Solitary instances. These exhibit the nature in subjects with nothing in common with other subjects but that nature; or which have no other similarity apart from that nature. (Two) Instances of transition. These are instances in which the nature previously did not exist, and is in transition to non-being. They are a good way to secure an affirmation. (Three) Revealing instances. These reveal the nature naked and independent, almost at the height of its power. (Four) Concealing instances are almost the opposite of revealing instances. (Five) Constitutive instances make up one species of a nature under investigation as a lesser Form. They are important because they contribute to forming definitions and divisions of natures. (Six) Instances of resemblance. These reveal resemblances between things in the actual object. (Seven) unique instances. These reveal bodies that have little connection with other things of the same kind. Every irregularity will depend on a common form. (Eight) Deviant instances. Errors and freaks of nature, where nature diverts from its course. They are wonders of individuals, rather than of species. (Nine) Borderline instances. These instances exhibit species of bodies that seem to be compounded of two species. (Ten) Instances of power, or man's contrivances or tools. These are the finished works of any art. A thorough survey of the liberal and mechanical arts is needed to enumerate them.
(Eleven) Instances of association and aversion. These exhibit a substance or thing that either attracts or repels the nature under investigation. They narrow down the scope of the affirmative, so we can recognize a nature as one that enters into the composition of such a body. (Twelve) Accessory instances. These mark how far a nature can do something. (Thirteen) instances of alliance or union. These unite natures thought to be separate by revealing that operations thought to belong to one nature also belong to others. (Fourteen) crucial instances. Sometimes the intellect cannot decide to which nature it should attribute the nature under investigation. Crucial instances reveal that one of the possible natures is permanent, and the other fitful and temporary. The latter can therefore be discarded. (Fifteen) Instances of divergence. These are separations of nature that most commonly occur. They declare the separation of a nature from a concrete instance with which it is commonly found, but settle nothing. Their value lies on showing up false forms.
The following five instances all assist the senses: (Sixteen) instances that open doors. These assist direct actions of sense, either to see what has not been seen, or to see further, or to see more accurately and distinctly. (Seventeen) summoning instances. These summon thing to present themselves that have not previously done so. They make sensible the non-sensible. (Eighteen) Instances of the road. These are instances which indicate discretely continuous motions in nature. These motions avoid observation rather than sense. For example, we should observe the hatching and development of eggs. (Nineteen) Instances of supplement or substitution. These are the instances that supply information when the senses have drawn a total blank. We resort to them when we have been unable to get proper instances. This substitution can occur by analogy. (Twenty) cleaving instances. They cleave nature apart, reminding the intellect of the subtlety of nature. For example, a little drop of ink can make a certain number of letters or lines.
The next instances are of particular value for the applied part of the enterprise. They have the general name of practical instances. They are divided into mathematical or measuring instances and benevolent instances, which economize on material and equipment, and direct the operative function to those things of most use to men. (Twenty-one) Instances of the rod or ruler, or instances of range or furthest limit. Things work at fixed and definite distances; it is valuable to observe and note them in every nature we seek. (Twenty-two) Running instances. They measure nature by moments of time. (Twenty- three) Instances of quantity. These are instances that measure powers by the quantities of bodies, and indicate what quantity of a body results in a certain amount of power. (Twenty-four) Instances of struggle, or instances of dominance. They point to alternating dominance and submission of powers, and point to which one is stronger and prevails, and which one is weaker and concedes. The motions of bodies are compounded and combined with one another. Bacon gives an account of the main forms of motion (the indestructibility of matter; bonding; liberty; matter; cohesion; gain; major / minor aggregation; avoidance; stimulation; configuration; passage; political spontaneous motion of rotation; trembling; rest) to show their respective strengths. We need to investigate why some motions dominate over others, and why they give way.
(Twenty-five) Suggestive instances. These are instances that point to human benefits. (Twenty-six) multipurpose instances. These are relevant to many topics, and so save a lot of work and new proofs. (Twenty-seven) magical instances. Instances in which the matter or efficient cause is slight in comparison with the result. They are something like a miracle, and Nature supplies them sparingly.
These are all of the privileged, or first-class instances. Bacon is dealing with logic, not philosophy, and logic trains the mind to dissect nature thoroughly, and discover the powers and actions of bodies and their laws evident in nature. This science takes its nature from the nature of the mind, and the nature of things. The use of the privileged instances tends towards either information or operation. In the informative aspect they assist either the understanding or the senses. Privileged instances designate, facilitate or measure practice. Some of the instances should be sought immediately; others only when a table of presentation has been drawn up. Bacon now intends to proceed to the aids and corrections of induction, then to concrete things, then to latent processes and structures. An improvement in the human condition will follow when human understanding comes of age and is freed from tutelage. The loss caused by the Fall can be repaired to an extent, by religion, and also by the arts and sciences.
Privileged instances represent the next stage in Bacon's inductive method. After tables of presentation have been drawn up, and the first harvest or interpretation made, the picture that the investigator has is still blurred. He may have some idea as to what he is looking for, but no firm proofs. Privileged instances help to clarify the situation. Bacon devotes a great deal of space to explaining each individually, but all share similar characteristics.
Privileged instances are examples of the nature in question that reveal that nature in a particularly clear way. Their clarity allows the investigator to identify the form he seeks more quickly and surely. Privileged instances depend on the investigator or his assistants performing experiments, which may in turn suggest other experiments. Some scholars have compared the role of privileged instances to that of individual law cases; after the general rules or ideas have been established, privileged instances refine and define the status of these general maxims. Julian Martin goes further than this, to suggest that much of Bacon's inductive method comes from his experience as a lawyer and politician.
The role of experiments in the search for privileged instances is important. Often, only a carefully designed experiment will reveal a key instance that will move the process of induction forward. Bacon describes and discusses several experiments in this part of the New Organon, involving expanding gases, heat expansion and thermometers. Also, as Lisa Jardine points out, Bacon discusses many key contemporary scientific issues, such as the action of tides, the microscope and magnetism. Many educated gentlemen took a passing interest in matters of natural philosophy in the seventeenth century, but Bacon seems to have been particularly well-informed. This merely emphasizes the fact that Bacon's inductive method relies as much on experiments and "practical" science as on theory.
One of the most interesting types of privileged instance is the crucial instance. Crucial instances come at a key point in the process of induction, when the intellect cannot decide to which of two possible natures the one under investigation should be assigned. This is a kind of "make or break" moment for the investigator, but the kind of experiment associated with a crucial instance reveals exactly which nature he should choose. Crucial instances, also known as instances of the finger post, point the way for the investigator.
Privileged instances can assist the senses to draw the correct conclusions, or suggest the correct experimental practice to follow. Although they can clarify things greatly, they are only the next stage in Bacon's method. You should imagine the whole process of induction as something like cutting a precious stone; the investigator begins with a mass of raw material and then applies more and more sophisticated processes to chip away at that mass to achieve the desired result.
However, the New Organon reveals little about how the process develops after the privileged instances. The end of Book Two gives few hints, apart from the idea that further aids to induction need to be applied. Exactly how his inductive method produces axioms is uncertain. Book Two ends with a rousing reference to the improvement in the human condition that will result, Bacon feels, from the completion of his project. He believes that increasing knowledge about nature will produce benefits that could reverse the Fall of man from the Garden of Eden after Adam and Eve. Many of Bacon's contemporaries believed that, after the Fall, the possibilities for knowledge and science were limited, but Bacon directly challenges this view. Unfortunately, the rest of theNew Organon remains fragmentary.