Here is a pseudocode declaration for a string array initialized with the given strings:
```
declare a string array named scientists
initialize scientists with values "Einstein", "Newton", "Copernicus", and "Kepler"
```
Alternatively, the declaration and initialization can be combined in one line:
```
declare a string array named scientists and initialize it with values "Einstein", "Newton", "Copernicus", and "Kepler"
```
In programming languages such as Java, the syntax for declaring and initializing a string array would be:
```java
String[] scientists = {"Einstein", "Newton", "Copernicus", "Kepler"};
```
In C#, the syntax would be:
```csharp
string[] scientists = {"Einstein", "Newton", "Copernicus", "Kepler"};
```
And so on for other programming languages.