How rationality is conceived and born in us:
This is brought about by means of an inflow of the Lord through heaven into whatever spiritual and worldly knowledge we have, lifting us up as a result. This lifting up depends on the useful things we do and on our love of them. Our rationality is born by means of truths, so the nature of the truths determines the nature of our rationality. Our rationality is opened and given form by truths that arise from living a good life; it is closed and destroyed by falsities that arise from living an evil life. Our being able to argue that this or that is true does not mean we are rational; we are rational if we are able to see and perceive whether something is actually true or not. We are not born with any truth, because we are not born with any goodness; we need to learn and absorb everything. Because of the deceptiveness of our senses and the persuasiveness of falsity, which lead to rationalizations and doubts, we are barely able to accept genuine truths and then become wise.
The beginning of our wisdom occurs when we start to turn our backs on rationalizations that deny what is true, and to cast aside our doubts. When our rational ability is not enlightened it scoffs at inner truths. Our truths can properly be called inner truths only when they have been rooted in our lives, and not merely because we know about them, even though some truths that we know about might be said to be of a deeper kind.
Within goodness there lies a capacity to grow in wisdom; if our lives have been devoted to doing what is good, we attain angelic wisdom after our departure from this world. Within every type of goodness countless other types of goodness lie hidden. From goodness countless things can be learned.
How truth multiplies as a result of goodness:
By means of truths and by means of living according to them, the goodness we have in early childhood becomes the goodness that belongs to wisdom. We can be moved by a desire for truth and we can be moved by a desire for goodness. What we are like when we are moved by a desire for truth and what we are like when we are moved by a desire for goodness. Which people can come to desire truth and which people cannot. All truths are arranged under some emotion that they have in common. In earthly-minded people a desire for truth and a desire for goodness are like brother and sister, while in spiritually minded people they are like husband and wife.
Pure truths are not to be found in us or even in angels—only in the Lord. Any truths that we have are only apparently true. The first truths we have are things that seem to be true according to our deceptive senses; we gradually shed these as we increase in wisdom. If we are devoted to what is good, the things we think are true are accepted as real truths by the Lord.
The substance and nature of things that seem to be truths:
Much of the literal meaning of the Word is adapted to suit the way things seem to people. The same truths can be more true for one individual, less true for another, and false for yet another because they have been distorted. By coordinating the impressions of our earthly self with those of our spiritual self, we can see whether the things we hold as true are actually true or not. How true our truths are varies depending on our ideas and concepts of them.
When a truth has been joined to goodness it vanishes from our memory because it has become part of our life. Truths can be joined to goodness only in a state of freedom. Truths are joined to goodness by means of the crises of the spirit we go through. All goodness makes a constant effort to put truths in their place and to be restored by means of an inversion of its state. Truths become unpleasant when their connection with goodness is cut off. It is hard for us to tell the difference between truth and goodness because it is hard for us to tell the difference between thinking and willing. In the Word, what is good is called the brother of what is true. From one point of view, whatever is good is called a lord and whatever is true is called a servant.
from New Jerusalem, Section 27