3219. When the angels are conversing about knowledges, and ideas, and influx, there then appear in the world of spirits as it were birds, formed in accordance with the subject of their discourse. Hence it is that in the Word "birds" signify rational things, or those which are of thought (see n. 40, 745, 776, 991). There were once presented to my view birds, one dark and unsightly, but two noble and beautiful; and when I saw them, there then fell upon me some spirits with such violence as to strike a tremor into my nerves and bones. I imagined that then, as several times before, evil spirits were assaulting me, with intent to destroy me; but this was not the case; for when the tremor ceased, together with the emotion of the spirits who fell upon me, I spoke with them, asking what was the matter.
 They said that they had fallen down from a certain angelic society in which there was discourse concerning thoughts and influx; and that they had held the opinion that things relating to thought flow in from without, that is, through the external senses, according to the appearance; whereas the heavenly society in which they were, held the opinion that they inflow from within; and as they (the speakers) were in falsity, they fell down-not that they were cast down, for the angels cast no one down from them, but being in falsity they fell down of themselves; and they said that this was the cause.
 By this it was given to know that discourse in heaven concerning thoughts and influx is represented by birds; and that of those who are in falsity by dark and unsightly birds; but that of those who are in the truth, by birds noble and beautiful. I was at the same time instructed that all things of thought inflow from within, and not from without, although it appears so; and I was told that it is contrary to order for the posterior to flow into the prior, or the grosser into the purer; thus for the body to inflow into the soul.