Like most numbers in the Bible, "six" can have various meanings depending on context, but has a couple that are primary. When used in relation to time -- six days, six hours, six years, etc. -- six generally represents a state of labor, struggle and conflict, especially the conflict involved with spiritual growth. The six days of creation, for instance, represent the stages we go through in our lives, working toward the peaceful seventh day, in which our evil desires are removed from us and we can rest. In most other references, six represents all desires for good and all the true ideas that come from those desires for good -- or in the contrary sense, all evil and all the resulting false thinking.

803. 'Birds, beasts, wild animals, and every creeping thing that creeps over the earth' means their persuasions, among which 'birds' means affections for falsity, 'beasts' evil desires, wild animals' pleasures, 'creeping thing that creeps' bodily and earthly interests. This becomes clear from what has been shown already about the meaning of birds and beasts - about birds in 40, and above at verses 14-15, of this chapter, and about beasts as well in those same verses, and also in 45, 46, 142, 143, 246. Since birds mean intellectual concepts, rational concepts, and factual knowledge, they also mean things that are the contrary, such as perverted rational concepts, falsities, and affections for falsity. The persuasions of the people before the Flood are described fully here, that is to say, they had within them affections for falsity, evil desires, pleasures, and bodily and earthly interests. All of these things are present in persuasions, though a person is not directly conscious of this, for he imagines that a false assumption, or persuasion of falsity, is some uncomplicated or quite general entity. He is much mistaken however, for the situation is altogether different. Every one of a person's affections derives its existence and character from the things of his understanding and at the same time from those of his will. As a result the whole person as regards all things of his understanding and all those of his will is present in every one of his affections, indeed in the most individual or least parts of them.

[2] This has been made quite clear to me from many experiences. For example, to mention but one, a spirit in the next life is able to recognize a person's character from merely one idea in that person's thinking. Indeed angels have the ability from the Lord to know anyone's character in an instant by merely looking at him; and they never make a mistake. From this it is clear that every one of a person's ideas, every affection, indeed every least part of his affection, is an image and replica of himself. That is, it contains something, closely or remotely, of the whole of his understanding and of the whole of his will. This then is how the dreadful persuasions of the people before the Flood are described: They had within them affections for falsity, also affections for evil (which are evil desires), as well as pleasures, and last of all bodily and earthly interests. All of these are present within such persuasions; and not only within persuasions in general but also within the most individual or least parts of persuasions, in which bodily and earthly interests are predominant. If anyone knew how much one false assumption or one persuasion of falsity contained he would be horrified. It is in a way an image of hell. But if they are the product of innocence or of ignorance, those falsities in him are easily dispersed.