'''0. The simplicity of Tcl stems from its simple syntax and processing model'''

The [Endekalogue] and the simple resolution and application of [[lindex $cmd 0]] to [[lrange $cmd 1 end]] is the fundamental form of Tcl.

'''1. The extensibility of Tcl stems from its processing model'''

[proc] {[upvar]; X; [[[uplevel] Y]]; [return];} is a skeleton which allows you to create and extend any tcl command or proc.

'''2. The universality of Tcl stems from the fact that values have [string] representation'''

It is not precisely true to say ''everything is a string'', but everything which has a value has a string value.  So any processing can be performed on strings.

'''2a. Tcl has a rich set of [string] operators'''

This enables X (1. above) to decide what to do in the surrounding processing scope, and Y to effect it.

'''3. Tcl has many powerful naming capabilities'''

'''3a.''' [proc] introduces and defines a functional name,

'''3b.''' [global] [upvar] [variable] [set] and [array] create named state.