The LaggedLink is a predicate transformer that takes a temporal predicate and shifts it in the past, or possibly in the future if the lag is negative. It is used to define the PLN semantics of SequentialAndLink and such.

## Format

```LaggedLink
P
T
```

where P is a temporal predicate and T is a time difference (maybe represented by a TimeNode, although we may want to introduce a TimeDifferenceNode).

## Semantics

Assuming for now a temporal predicate with two arguments

```P(x, t)
```

where x is atemporal, and t represents time, then

```LaggedLink
P
T
```

is equivalent to

```LambdaLink
x, t
P(x, t-T)
```

## Example

Let us define the temporal predicate

```tall(p, t)
```

representing if person p is tall, perhaps to some degree, at time t.

Then

```(Lagged tall 1y)(John, Now)
```

represents the tallness of John a year ago. While

```(Lagged tall -1y)(Mary, Now)
```

represents the tallness of Mary a year from now. And

```(Lagged tall 1d)(Eva, Tomorrow)
```

represents the tallness of Eva now.