But we may observe, that, though the rule of the assignment of property to the present possessor be natural, and by that means useful, yet its utility extends not beyond the first formation of society; nor would any thing be more pernicious than the constant observance of it; by which restitution would be excluded, and every injustice would be authorized and rewarded. We must, therefore, seek for some other circumstance, that may give rise to property after society is once established; and of this kind I find four most considerable, viz. Occupation, Prescription, Accession, and Succession. We shall briefly examine each of these, beginning with _occupation_. The possession of all external goods is changeable and uncertain; which is one of the most considerable impediments to the establishment of society, and is the reason why, by universal agreement, express or tacit, men restrain themselves by what we now call the rules of justice and equity. The misery of the condition which precedes this restraint, is the cause why we submit to that remedy as quickly as possible; and this affords us an easy reason why why annex the idea of property to the first possession, or to _occupation_. Men are unwilling to leave property in suspense, even for the shortest time, or open the least door to violence and disorder. To which we may add, that the first possession always engages the attention most; and did we neglect it, there would be no colour of reason for assigning property to any succeeding possession.[2] There remains nothing but to determine exactly what is meant by possession; and this is not so easy as may at first sight be imagined. We are said to be in possession of any thing, not only when we immediately touch it, but also when we are so situated with respect to it, as to have it in our power to use it; and may move, alter, or destroy it, according to our present pleasure or advantage. This relation, then, is a species of cause and effect; and as property is nothing but a stable possession, derived from the rules of justice, or the conventions of men, 'tis to be considered as the same species of relation. But here we may observe, that, as the power of using any object becomes more or less certain, according as the interruptions we may meet with are more or less probable; and as this probability may increase by insensible degrees, 'tis in many cases impossible to determine when possession begins or ends; nor is there any certain standard by which we can decide such controversies. A wild boar that falls into our snares, is deemed to be in our possession if it be impossible for him to escape. But what do we mean by impossible? How do we separate this impossibility from an improbability? And how distinguish that exactly from a probability? Mark the precise limits of the one and the other, and show the standard, by which we may decide all disputes that may arise, and, as we find, by experience, frequently do arise upon this subject.[3]